Journal Article Series (JA)

Strong suppression of heat conduction in a laboratory replica of galaxy-cluster turbulent plasmas

2025-04-08T04:20:20Z

Strong suppression of heat conduction in a laboratory replica of galaxy-cluster turbulent plasmas Meinecke, J.; Tzeferacos, P.; Ross, J.S.; Bott, A.F.A.; Feister, S.; Park, H.-S.; Bell, A.R.; Blandford, R.; Berger, R.L.; Bingham, R.; Casner, A.; Chen, L.E.; Foster, J.; Froula, D.H.; Goyon, C.; Kalantar, D.; Koenig, M.; Lahmann, Brandon; Li, Chi-Kang; Lu, Y.; Palmer, C.A.J.; Petrasso, Richard D.; Poole, H.; Remington, B.; Reville, B.; Reyes, A.; Rigby, A.; Ryu, D.; Swadling, G.; Zylstra, A.; Miniati, F.; Sarkar, S.; Schekochihin, A.A.; Lamb, D.Q.; Gregori, G. In conventional gases and plasmas, it is known that heat fluxes are proportional to temperature gradients, with collisions between particles mediating energy flow from hotter to colder regions and the coefficient of thermal conduction given by Spitzer’s theory. However, this theory breaks down in magnetized, turbulent, weakly colli- sional plasmas, although modifications are difficult to predict from first principles due to the complex, multiscale nature of the problem. Understanding heat transport is important in astrophysical plasmas such as those in gal- axy clusters, where observed temperature profiles are explicable only in the presence of a strong suppression of heat conduction compared to Spitzer’s theory. To address this problem, we have created a replica of such a sys- tem in a laser laboratory experiment. Our data show a reduction of heat transport by two orders of magnitude or more, leading to large temperature variations on small spatial scales (as is seen in cluster plasmas). Submitted for publication in Science Advances

National Diagnostic Working Group (NDWG) for inertial confinement fusion (ICF)/high-energy density (HED) science: The whole exceeds the sum of its parts

2025-04-07T09:00:08Z

National Diagnostic Working Group (NDWG) for inertial confinement fusion (ICF)/high-energy density (HED) science: The whole exceeds the sum of its parts Kilkenny, K.D.; Hsing, W.W.; Batha, S.; Rochau, G.A.; Sangster, T.C.; Bell, P.M.; Bradley, D.K.; Chen, H.; Frenje, Johan A.; Gatu Johnson, Maria; Glebov, V. Yu; Leeper, R.J.; Mackinnon, A.J.; Regan, S.P.; Ross, J.S. The National Diagnostic Working Group (NDWG) has led the effort to fully exploit the major inertial confinement fusion/high-energy density facilities in the US with the best available diagnostics. These diagnostics provide key data used to falsify early theories for ignition and suggest new theories, recently leading to an experiment that exceeds the Lawson condition required for ignition. The factors contributing to the success of the NDWG, collaboration and scope evolution, and the methods of accomplishment of the NDWG are discussed in this Review. Examples of collaborations in neutron and gamma spectroscopy, x-ray and neutron imaging, x-ray spectroscopy, and deep-ultraviolet Thomson scattering are given. An abbreviated history of the multi-decade collaborations and the present semiformal management framework is given together with the latest National Diagnostic Plan. Submitted for publication in Review of Scientific Instruments

SPARC X-ray diagnostics: technical and functional overview

2025-04-07T09:27:16Z

SPARC X-ray diagnostics: technical and functional overview Vezinet, D.; Perks, C.J.; Panontin, E.; Normile, S.; Tinguely, R. Alex; Rice, John E.; Reinke, M.; Cario, M.; Raimond, J.; Hoffman, A.; Dubas, E.; Saltos, A.; Kennedy, R. An overview is given of SPARC’s three main X-ray diagnostics with a focus on the functions they fulfill with respect to tokamak operation. The first is an in-vessel soft X-ray tomography diagnostic, aimed at providing early-campaign information on plasma position, MHD activity and impurity content. The second is an ex-vessel set of hard X-ray scintillators aimed at detecting the presence of runaway electrons, in particular during plasma startup phases. The third is a set of X-ray Bragg spectrometers, located outside of the Tokamak Hall, aimed at informing on the ion temperature as an indirect constraint to reduce uncertainties on the fusion power, on providing plasma rotation velocity estimates and on observing impurity emission. Finally, more technical details are given on the beamlines at the end of which the spectrometers are located. It is explained how their design allows to ensure tritium containment and limiting neutron radiation while providing a straight view into the plasma that can also be used for for testing new innovative sensors. Submitted for publication in Review of Scientific Instruments

Learning from Each Other: Cross-Cutting Diagnostic Development Activities Between Magnetic and Inertial Confinement Fusion

2025-04-07T08:38:56Z

Learning from Each Other: Cross-Cutting Diagnostic Development Activities Between Magnetic and Inertial Confinement Fusion Gatu Johnson, Maria; Schlossberg, D.; Appelbe, B.; Ball, J.; Bitter, M.; Casey, D.T.; Celora, A.; Ceurvorst, L.; Chen, H.; Conroy, S.; Crilly, A.; Croci, G.; Dal Molin, A.; Delgado-Aparicio, L.; Efthimion, P.; Eriksson, B.; Eriksson, J.; Forrest, C.; Fry, C.; Frenje, Johan A.; Gao, L.; Geppert-Kleinrath, H.; Geppert-Kleinrath, V.; Gilson, E.; Heuer, P.V.; Hill, K.; Khater, H.; Kraus, F.; Laggner, F.; Lawrence, Y.; Mackie, S.; Meaney, K.; Milder, A.; Moore, A.; Nocente, M.; Pablant, N.; Panontin, E.; Rebai, M.; Reichelt, Benjamin L.; Reinke, M.; Rigamonti, D.; Ross, J.S.; Rubery, M.; Russell, L.; Tardocchi, M.; Tinguely, R. Alex; Wink, Christopher W. Inertial and Magnetic Confinement Fusion (ICF and MCF) follow different paths toward goals that are largely common. In this paper, the claim is made that progress can be accelerated by learning from each other across the two fields. Examples of successful cross-community knowledge transfer are presented that highlight the gains from working together, specifically in the areas of high-resolution x-ray imaging spectroscopy and neutron spectrometry. Opportunities for near and mid-term collaboration are identified, including in Chemical Vapor Deposition (CVD) diamond detector technology, using gamma rays to monitor fusion gain, handling neutron-induced backgrounds and developing radiation hard technology, and collecting fundamental supporting data needed for diagnostic analysis. Fusion research is rapidly moving into the igniting and burning regimes, posing new opportunities and challenges for ICF and MCF diagnostics. This includes new physics to probe, such as alpha heating; increasingly harsher environmental conditions; and (in the slightly longer term) the need for new plant monitoring diagnostics. Substantial overlap is expected in all of these emerging areas, where joint development across the two subfields as well as between public and private researchers can be expected to speed up advancement for all. Submitted for publication in Review of Scientific Instruments

A knock-on deuteron imager for measurements of fuel and hotspot asymmetry in direct-drive inertial confinement fusion implosions (invited)

2025-04-08T04:45:50Z

A knock-on deuteron imager for measurements of fuel and hotspot asymmetry in direct-drive inertial confinement fusion implosions (invited) Rinderknecht, H.G.; Heuer, P.V.; Kunimune, Justin H.; Adrian, Patrick J.; Knauer, J.P.; Theobald, W.; Fairbanks, R.; Brannon, B.; Ceurvorst, L.; Gopalaswamy, V.; Williams, C.A.; Radha, P.B.; Regan, S.P.; Gatu Johnson, Maria; Séguin, Frederick H.; Frenje, Johan A. A knock-on deuteron imager (KoDI) has been implemented to measure the fuel and hotspot asymmetry of cryogenic inertial confinement fusion implosions on OMEGA. Energetic neutrons produced by D–T fusion elastically scatter (“knock on”) deuterons from the fuel layer with a probability that depends on ρR. Deuterons above 10 MeV are produced by near-forward scattering, and imaging them is equivalent to time-integrated neutron imaging of the hotspot. Deuterons below 6 MeV are produced by a combination of side scattering and ranging in the fuel, and encode information about the spatial distribution of the dense fuel. The KoDI instrument consists of a multi-penumbral aperture positioned 10–20 cm from the implosion using a ten-inch manipulator and a detector pack at 350 cm from the implosion to record penumbral images with magnification of up to 35×. Range filters and the intrinsic properties of CR-39 are used to distinguish different charged-particle images by energy along the same line of sight. Image plates fielded behind the CR-39 record a 10 keV x-ray image using the same aperture. A maximum-likelihood reconstruction algorithm has been implemented to infer the source from the projected penumbral images. The effects of scattering and aperture charging on the instrument point-spread function are assessed. Synthetic data are used to validate the reconstruction algorithm and assess an appropriate termination criterion. Significant aperture charging has been observed in the initial experimental dataset, and increases with aperture distance from the implosion, consistent with a simple model of charging by laser-driven EMP. Submitted for publication in Review of Scientific Instruments

First application of a digital mirror Langmuir probe for real-time plasma diagnosis

2025-04-07T09:05:36Z

First application of a digital mirror Langmuir probe for real-time plasma diagnosis McCarthy, William; Golfinopoulos, T.; Woller, K.B.; Vincent, C.; Kuang, Adam Q.; Labombard, Brian For the first time, a digital Mirror Langmuir probe (MLP) has successfully sampled plasma temperature, ion saturation current, and floating potential together on a single probe tip in real time in a radio-frequency driven helicon linear plasma device. This is accomplished by feedback control of the bias sweep to ensure a good fit to I-V characteristics with a high frequency, high power digital amplifier and field-programmable gate array (FPGA) controller. Measurements taken by the MLP were validated by a low speed I-V characteristic manually collected during static plasma conditions. Plasma fluctuations, induced by varying the axial magnetic field (f̃ = 10 Hz), were also successfully monitored with the MLP. Further refinement of the digital MLP pushes it towards a turn-key system that minimizes the time to deployment and lessens the learning curve, positioning the digital MLP as a capable diagnostic for the study of low radio-frequency plasma physics. These demonstrations bolster confidence in fielding such digital MLP diagnostics in magnetic confinement experiments with high spatial and adequate temporal resolution such as edge plasma, scrape-off layer, and divertor probes. Submitted for publication in Review of Scientific Instruments

Characterizing x-ray transmission through filters used in high energy density physics diagnostics

2025-04-08T04:13:07Z

Characterizing x-ray transmission through filters used in high energy density physics diagnostics Pearcy, J.; Kabadi, N.; Birkel, A.; Adrian, P.; Lahmann, B.; Reichelt, B.; Johnson, T.M.; Sutcliffe, G.; Kunimune, Justin H.; Gatu Johnson, Maria; Bose, A.; Li, Chi-Kang We report on the design and implementation of a new system used to characterize the energy-dependent x-ray transmission curve, Θ(E), through filters used in high-energy density physics diagnostics. Using an Amptek X-123-CdTe x-ray spectrometer together with a partially depleted silicon surface barrier detector, both the energy spectrum and total emission of an x-ray source have been accurately measured. By coupling these detectors with a custom PROTO-XRD x-ray source with interchangeable cathodes, accurate characterizations of Θ(E) for filters of varying materials and thicknesses have been obtained. The validity of the technique has been confirmed by accurately reproducing areal densities for high-purity filters with known x-ray transmission properties. In this paper, the experimental setup is described and the results of absorption calibrations performed on a variety of different filters are presented. Submitted for publication in Review of Scientific Instruments

Interpolating individual line-of-sight neutron spectrometer measurements onto the “sky” at the National Ignition Facility (NIF)

2025-04-07T09:02:47Z

Interpolating individual line-of-sight neutron spectrometer measurements onto the “sky” at the National Ignition Facility (NIF) Hartouni, E.P.; Bionta, R.M.; Casey, D.T.; Eckart, M.J.; Gatu Johnson, Maria; Grim, G.P.; Hahn, K.D.; Jeet, J.; Kerr, S.M.; Kritcher, A.L.; MacGowan, B.J.; Moore, A.S.; Munro, D.H.; Schlossberg, D.J.; Zylstra, A. Nuclear diagnostics provide measurements of inertial confinement fusion (ICF) implosions used as metrics of performance for the shot. The interpretation of these measurements for shots with low mode asymmetries requires a way of combining the data to produce a “sky map” where the individual line-of-sight values are used to interpolate to other positions in the sky. These interpolations can provide information regarding the orientation of the low mode asymmetries. We describe the interpolation method, associated uncertainties, and the correlations between different metrics, e.g. Tion, down scatter ratio (DSR) and hot-spot velocity direction. This work is also related to recently reported studies [H. G. Rinderknecht et al., Phys. Rev. Lett. 124, 145002 (2020) and K. M. Woo et al., Phys. Plasmas 27, 062702 (2020)] of low mode asymmetries. We report an analysis that makes use of a newly commissioned line-of-sight, a scheme for incorporating multiple neutron spectrum measurement types, and recent work on the sources of implosion asymmetry to provide a more complete picture of implosion performance. Submitted for publication in Review of Scientific Instruments

Quantum Lattice Representation for the Curl Equations of Maxwell Equations

2025-04-07T09:27:21Z

Quantum Lattice Representation for the Curl Equations of Maxwell Equations Vahala, George; Hawthorne, John; Vahala, Linda; Ram, Abhay K.; Soe, Min A quantum lattice representation (QLA) is devised for the initial value problem of one-dimensional (1D) propagation of an electromagnetic disturbance in a scalar dielectric medium satisfying directly only the two curl equations of Maxwell. It si found that only 4 qubits/node are required. The collision, streaming, and potential operators are determined so as to recover the two curl equations to second order. Both polarizations are considered. Submitted for publication in Radiation Effects and Defects in Solids

Building a Three-Dimensional Quantum Lattice Algorithm for Maxwell Equations

2025-04-08T04:23:15Z

Building a Three-Dimensional Quantum Lattice Algorithm for Maxwell Equations Vahala, George; Valhala, Linda; Soe, Min; Ram, Abhay K. A three-dimensional quantum lattice algorithm (QLA) for electromagnetic wave propagation is being developed by stitching together the individual QLAs for 1D wave propagation in the three orthogonal Cartesian directions. Submitted for publication in Radiation Effects and Defects in Solids

Electron heating in kinetic-Alfvén-wave turbulence

2025-04-07T08:42:12Z

Electron heating in kinetic-Alfvén-wave turbulence Zhou, Muni; Liu, Zhuo; Loureiro, Nuno F. We report analytical and numerical investigations of sub-ion-scale turbulence in low-beta plasmas using a rigorous reduced kinetic model. We show that efficient electron heating occurs, and is primarily due to Landau damping of kinetic Alfv\'en waves, as opposed to Ohmic dissipation. This collisionless damping is facilitated by the local weakening of advective nonlinearities and the ensuing unimpeded phase mixing near intermittent current sheets, where free energy concentrates. The linearly damped energy of electromagnetic fluctuations at each scale explains the steepening of their energy spectrum with respect to a fluid model where such damping is excluded (i.e., a model that imposes an isothermal electron closure). The use of a Hermite-polynomial representation to express the velocity-space dependence of the electron distribution function enables us to obtain an analytical, lowest-order solution for the Hermite moments of the distribution, which is borne out by numerical simulations. Submitted for publication in PNAS: Proceedings of the National Academy of Sciences of the United States of America

On the minimum transport required to passively suppress runaway electrons in SPARC disruptions

2025-04-07T08:30:39Z

On the minimum transport required to passively suppress runaway electrons in SPARC disruptions Tinguely, R. Alex; Pusztai, I.; Izzo, V.A.; Särkimäki, K.; Fülöp, T.; Garnier, D.T.; Granetz, R.S.; Hoppe, M.; Paz-Soldan, C.; Sunström, A.; Sweeney, Ryan In [V.A. Izzo et al 2022 Nucl. Fusion 62 096029], state-of-the-art modeling of thermal and current quench (CQ) MHD coupled with a self-consistent evolution of runaway electron (RE) generation and transport showed that a non-axisymmetric (n = 1) in-vessel coil could passively prevent RE beam formation during disruptions in SPARC, a compact high- field tokamak projected to achieve a fusion gain Q > 2 in DT plasmas. However, such suppression requires nite transport of REs within magnetic islands and re-healed flux surfaces; conservatively assuming zero transport in these regions leads to an upper bound of RE current ~1 MA compared to ~8.7 MA of pre-disruption plasma current. Further investigation fi nds that core-localized electrons, within r/a < 0.3 and with kinetic energies ~0.2-15 MeV, contribute most to the RE plateau formation. Yet only a relatively small amount of transport, i.e. a diffusion coefficient ~18 m^2/s, is needed in the core to fully mitigate these REs. Properly accounting for (i) the CQ electric field's effect on RE transport in islands and (ii) the contribution of significant RE currents to disruption MHD may help achieve this. Submitted for publication in Plasma Physics and Controlled Fusion

Demonstration of TNSA proton radiography on the National Ignition Facility Advanced Radiographic Capability (NIF-ARC) laser

2025-04-08T04:31:14Z

Demonstration of TNSA proton radiography on the National Ignition Facility Advanced Radiographic Capability (NIF-ARC) laser Simpson, R.A.; Mariscal, D.A.; Kim, J.; Scott, G.G.; Williams, G.J.; Grace, E.; McGuffey, C.; Wilks, S.; Kemp, A.; Lemos, N.; Djordjevic, B.Z.; Folsom, E.; Kalantar, D.; Zacharias, R.; Pollock, B.; Moody, J.; Beg, F.; Morace, A.; Iwata, N.; Sentoku, Y.; Manuel, M. J.-E.; Mauldin, M.; Quinn, M.; Youngblood, K.; Gatu Johnson, Maria; Lahmann, B.; Haefner, C.; Neely, D.; Ma, T. Proton radiography using short-pulse laser drivers is an important tool in high-energy density (HED) science for dynamically diagnosing key characteristics in plasma interactions. Here we detail the first demonstration of target-normal sheath acceleration (TNSA)-based proton radiography the NIF-ARC laser system aided by the use of compound parabolic concentrators (CPCs). The multi-kJ energies available at the NIF-ARC laser allows for a high-brightness proton source for radiography and thus enabling a wide range of applications in HED science. In this demonstration, proton radiography of a physics package was performed and this work details the spectral properties of the TNSA proton probe as well as description of the resulting radiography quality. Submitted for publication in Plasma Physics and Controlled Fusion

High resolution density pedestal measurements during edge localized modes by short-pulse reflectometry in the TCV tokamak

2025-04-07T09:24:05Z

High resolution density pedestal measurements during edge localized modes by short-pulse reflectometry in the TCV tokamak Molina Cabrera, Pedro A.; Labit, B.; Coda, S.; Porte, L. This publication presents high spatio-temporal resolution (mm/μs) density profile measurements of the pedestal top during type I, III, and small edge localized mode (ELM) H-mode plasmas in the Tokamak à Configuration Variable (TCV). These measurements were performed using a novel short-pulse reflectometer. Average inter-ELM density profiles are obtained via conditional averaging using the Dα trace as ELM indicator. Changes to the pedestal density profile gradients prior to type-III ELMs reveal unique pedestal dynamics leading to the ELM crash which can provide important experimental data for validation of non-linear MHD ELM simulations. The small-ELM scenario is found to feature a ∼25-35 kHz quasi-coherent density fluctuation near the separatrix rho_psi ∼0.993-1.05 not observed during a similar type-I ELM discharge. This oscillation is also found in low-field-side magnetic pick- up probes displaying a ballooning character and n=+1 toroidal mode number. This oscillation could help explain the markedly different pedestal dynamics observed in the small-ELM regime. Submitted for publication in Plasma Physics and Controlled Fusion

Nuclear diagnostics for Inertial Confinement Fusion (ICF) plasmas

2025-04-07T08:30:08Z

Nuclear diagnostics for Inertial Confinement Fusion (ICF) plasmas Frenje, Johan A. The field of nuclear diagnostics for Inertial Confinement Fusion (ICF) is broadly reviewed from its beginning in the seventies to present day. During this time, the sophistication of the ICF facilities and the suite of nuclear diagnostics have substantially evolved, generally a consequence of the efforts and experience gained on previous facilities. As the fusion yields have increased several orders of magnitude during these years, the quality of the nuclear-fusion-product measurements has improved significantly, facilitating an increased level of understanding about the physics governing the nuclear phase of an ICF implosion. The field of ICF has now entered an era where the fusion yields are high enough for nuclear measurements to provide spatial, temporal and spectral information, which have proven indispensable to understanding the performance of an ICF implosion. At the same time, the requirements on the nuclear diagnostics have also become more stringent. To put these measurements into context, this review starts by providing some historical remarks about the field of ICF and the role of nuclear diagnostics, followed by a brief overview of the basic physics that characterize the nuclear phase and performance of an ICF implosion. A technical discussion is subsequently presented of the neutron, gamma-ray, charged-particle and radiochemistry diagnostics that are, or have been, routinely used in the field of ICF. This discussion is followed by an elaboration of the current view of the next-generation nuclear diagnostics. Since the seventies, the overall progress made in the areas of nuclear diagnostics and scientific understanding of an ICF implosion has been enormous, and with the implementation of new high-fusion-yield facilities world-wide, the next-generation nuclear diagnostics will play an even more important role for decades to come. Submitted for publication in Plasma Physics and Controlled Fusion

First observations from the Kr multi-monochromatic X-ray imager for time and spatially resolved diagnosis of hot implosion cores

2025-04-07T08:43:46Z

First observations from the Kr multi-monochromatic X-ray imager for time and spatially resolved diagnosis of hot implosion cores Gallardo-Diaz, E.; Mancini, R.C.; Clapp, J.; Adrian, Patrick J.; Evans, Tucker E.; Frenje, Johan A.; Florido, R.; Kruse, M.K.G.; Nagayama, T. This paper presents initial findings from the recently deployed Kr Multi-Monochromatic X-ray Imager (MMI) at the Omega facility. The experiment focuses on exploring implosion dynamics in exploding pusher capsules at three distinct initial gas fill densities. Utilizing time-gated and spatially integrated measurements, core size, electron temperature (Te), and electron densities (ne) are extracted through the analysis of the spectral region encompassing the Kr Heα and its satellite lines. A comprehensive spectral database, incorporating atomic kinetics, spectroscopic quality radiation trans- port, and Stark-broadened line shapes, has been developed for rigorous data analysis. These measurements underscore the utility of the new Kr MMI instrument which combined with sophisticated analysis techniques enables the diagnosis of plasma conditions at Te > 2000 eV, thereby extending the capabilities beyond the prior Ar MMI design. This is an important stepping stone for achieving time-gated and space-resolved diagnostics of electron temperature, electron density, and heat transport in high temperature implosion cores. Submitted for publication in Physics of Plasmas

Empirical probability and machine learning analysis of m, n = 2, 1 tearing mode onset parameter dependence in DIII-D H-mode scenarios

2025-04-07T08:51:39Z

Empirical probability and machine learning analysis of m, n = 2, 1 tearing mode onset parameter dependence in DIII-D H-mode scenarios Bardóczi, L.; Richner, N.J.; Zhu, Jinxiang; Rea, Cristina; Logan, N.C. m, n = 2, 1 tearing mode onset empirical probability and machine learning analyses of a multiscenario DIII-D database of over 14 000 H- mode discharges show that the normalized plasma beta, the rotation profile, and the magnetic equilibrium shape have the strongest impact on the 2,1 tearing mode stability, in qualitative agreement with neoclassical tearing modes (m and n are the poloidal and toroidal mode numbers, respectively). In addition, 2,1 tearing modes are most likely to destabilize when n > 1 tearing modes are already present in the core plasma. The covariance matrix of tearing sensitive plasma parameters takes a nearly block-diagonal form, with the blocks incorporating thermodynamic, current and safety factor profile, separatrix shape, and plasma flow parameters, respectively. This suggests a number of paths to improved stability at fixed pressure and edge safety factor primarily by preserving a minimum of 1 kHz differential rotation, increasing the minimum safety factor above unity, using upper single null magnetic configuration, and reducing the core impurity radiation. In addition, lower triangularity, lower elongation, and lower pedestal pressure may also help to improve stability. The electron and ion temperature, collisionality, resistivity, internal inductance, and the parallel current gradient appear to only weakly correlate with the 2,1 tearing mode onsets in this database. Submitted for publication in Physics of Plasmas

Three dimensional low-mode areal-density non-uniformities in indirect-drive implosions at the National Ignition Facility

2025-04-07T09:16:10Z

Three dimensional low-mode areal-density non-uniformities in indirect-drive implosions at the National Ignition Facility Casey, D.T.; Landen, O.L.; Hartouni, E.; Bionta, R.M.; Hahn, K.D.; Volegov, P.L.; Fittinghoff, D.N.; Geppert-Kleinrath, V.; Wilde, C.H.; Milovich, C.H.; Smalyuk, V.A.; Field, J.E.; Hurricane, O.A.; Zylstra, A.B.; Kritcher, A.L.; Clark, D.S.; Young, C.V.; Nora, R.C.; Callahan, D.A.; MacGowan, B.J.; Munro, D.H.; Spears, B.K.; Peterson, J.L.; Gaffney, J.A.; Humbird, K.D.; Kruse, M.K.G.; Moore, A.S.; Schlossberg, D.J.; Gatu Johnson, Maria; Frenje, Johan A. To achieve hotspot ignition, an inertial confinement fusion (ICF) implosion must achieve high hotspot pressure that is inertially confined by a dense shell of DT fuel. This requires a symmetric implosion having high in-flight shell velocity and high areal density at stagnation. The size of the driver and scale of the capsule required can be minimized by maintaining a high efficiency of energy coupling from the imploding shell to the hotspot. Significant 3D low mode asymmetries, however, are commonly observed in indirect-drive implosions and reduce the coupling of shell kinetic energy to the hotspot. To better quantify the magnitudes and impacts of shell density asymmetries, we have developed new analysis techniques and analytic models [Hurricane et. al., Physics of Plasmas 27 (6), 062704 (2020)]. To build confidence in the underlying data, we have also developed an analytic neutron transport model to cross-compare two independent measurements of asymmetry, which shows excellent agreement across shots for mode-1 (l=1). This work also demonstrates that asymmetry can introduce potential sampling bias into down-scattered ratio measurements causing the solid-angle-average and uncertainty-weighted-average down-scattered ratios to differ significantly. Diagnosing asymmetries beyond mode-1 (l>1) presents significant challenges. Using new diagnostic instruments and analysis techniques, however, evidence of significant Legendre mode P2 (l=2, m=0) and additional 3D asymmetries (l>1, m≠0) are beginning to emerge from the high precision activation diagnostic data (RTNADs) and down-scattered neutron imaging data. Submitted for publication in Physics of Plasmas

Shock Ignition Laser-Plasma Interactions in Ignition-Scale Plasmas

2025-04-08T04:43:56Z

Shock Ignition Laser-Plasma Interactions in Ignition-Scale Plasmas Scott, R.H.H.; Glize, K.; Antonelli, L.; Khan, M.; Theobald, W.; Wei, M.; Betti, R.; Stoeckl, C.; Seaton, A.G.; Arber, T.D.; Barlow, D.; Goffrey, T.; Bennett, K.; Garbett, W.; Atzeni, S.; Casner, A.; Batani, D.; Li, Chi-Kang; Woolsey, N. We use a subignition scale laser, the 30 kJ Omega, and a novel shallow-cone target to study laser-plasma interactions at the ablation-plasma density scale lengths and laser intensities anticipated for direct drive shock-ignition implosions at National Ignition Facility scale. Our results show that, under these conditions, the dominant instability is convective stimulated Raman scatter with experimental evidence of two plasmon decay (TPD) only when the density scale length is reduced. Particle-in-cell simulations indicate this is due to TPD being shifted to lower densities, removing the experimental back-scatter signature and reducing the hot-electron temperature. The experimental laser energy-coupling to hot electrons was found to be 1%– 2.5%, with electron temperatures between 35 and 45 keV. Radiation-hydrodynamics simulations employing these hot-electron characteristics indicate that they should not preheat the fuel in MJ-scale shock ignition experiments. Submitted for publication in Physical Review Letters

Dyson maps and unitary evolution for Maxwell equations in tensor dielectric media

2025-04-07T08:31:51Z

Dyson maps and unitary evolution for Maxwell equations in tensor dielectric media Koukoutsis, Efstratios; Hizanidis, Kyriakos; Ram, Aghay K.; Vahala, George The propagation and scattering of electromagnetic waves in dielectric media is of theoretical and experimental interest in a wide variety of fields. An understanding of observational results generally requires a numerical solution of Maxwell equations - usually implemented on conventional computers using sophisticated numerical algorithms. In recent years, advances in quantum information science and in the development of quantum computers have piqued curiosity about taking advantage of these resources for an alternate numerical approach to Maxwell equations. This requires a reformulation of the classical Maxwell equations into a form suitable for quantum computers which, unlike conventional computers, are limited to unitary operations. In this paper, a unitary framework is developed for the propagation of electromagnetic waves in a spatially inhomogeneous, passive, nondispersive, and anisotropic dielectric medium. For such a medium, generally, the evolution operator in the combined Faraday-Ampere equations is not unitary. There are two steps needed to convert this equation into a unitary evolution equation. In the first step, a weighted Hilbert space is formulated in which the generator of dynamics is a pseudo-Hermitian operator. In the second step, a Dyson map is constructed which maps the weighted-physical-Hilbert space to the original Hilbert space. The resulting evolution equation for the electromagnetic wave fields is unitary. Utilizing the framework developed in these steps, a unitary evolution equation is derived for electromagnetic wave propagation in a uniaxial dielectric medium. The resulting form is suitable for quantum computing. Submitted for publication in Physical Review A

Multi-code estimation of DTT edge transport parameters

2025-04-08T04:31:01Z

Multi-code estimation of DTT edge transport parameters Balbinot, L.; Rubino, G.; Casiraghi, I.; Meineri, C.; Frassinetti, L.; Aucone, L.; Mantica, P.; Innocente, P.; Wigram, Mike; JET contributors; Alcator C-Mod Team The main goal of the Divertor Tokamak Test facility (DTT) is to operate with a high value of power-exhaust relevant parameter PSOL/R in plasma scenarios similar to those foreseen for the Demonstration Fusion Power Plant (DEMO) in terms of low collisionality and neutral opacity. For these unique characteristics, accurate modelling of the principal scenario is necessary for machine designing. In edge numerical codes, cross-field transport profiles have a high impact on modelling results. This work aims at providing a coherent set of transport parameters for DTT full-power (FP) single-null (SN) scenario edge modelling. To evaluate such parameters for DTT, a transport analysis on the current machine has been performed using SOLEDGE2D-EIRENE and SOLPS-ITER. The transport parameters to be used in the simulations of the DTT single-null scenario were selected using two complementary methods. The first is the modelling of JET and Alcator C-Mod (C-Mod) with SOLEDGE2DEIRENE and SOLPS-ITER, validating transport parameters by comparing modelling results to experimental data from pulses which are considered DTT-relevant. JET pulses were selected with the highest auxiliary input power (from 29 to 33 MW), plasma current and toroidal field to better match DTT parameters; nitrogen and neon seeded pulses were selected to check possible seeding material dependencies. The considered C-Mod pulse better matches DTT plasma density and neutral opacity. Transport parameters are then scaled to DTT according to scaling laws. The second method derives the transport parameters by tuning their values inside the DTT separatrix to reproduce the pedestal profiles predicted by the EPED model via the Europed code and applied in DTT. The derived set of DTT transport parameters is consistent with the results obtained by modelling present machines, reproduces the expected heat flux decay length in detached conditions and, inside the separatrix, reproduces the predicted pedestal using transport parameters which are coherent with what is predicted by the quasi-linear turbulent model QuaLiKiz. Submitted for publication in Nuclear Materials and Energy

Design of Passive and Structural Conductors for Tokamaks Using Thin-Wall Eddy Current Modeling

2025-04-07T09:11:04Z

Design of Passive and Structural Conductors for Tokamaks Using Thin-Wall Eddy Current Modeling Battey, A.F.; Hansen, C.; Garnier, D.; Weisberg, D.; Paz-Soldan, C.; Sweeney, Ryan; Tinguely, R. Alex; Creely, A.J. A new three-dimensional electromagnetic modeling tool (ThinCurr) has been developed using the existing PSI-Tet finite-element code in support of conducting structure design work for both the SPARC and DIII-D tokamaks. Within this framework a 3D conducting structure model was created for both the SPARC and DIII-D tokamaks in the thin-wall limit. This model includes accurate details of the vacuum vessel and other conducting structural elements with realistic material resistivities. This model was leveraged to support the design of a passive runaway electron mitigation coil (REMC), studying the effect of various design parameters, including coil resistivity, current quench duration, and plasma vertical position, on the effectiveness of the coil. The REMC is a non-axisymmetric coil designed to passively drive large non-axisymmetric fields during the plasma disruption thereby destroying flux surfaces and deconfining RE seed populations. These studies indicate that current designs should apply substantial 3D fields at the plasma surface during future plasma current disruptions as well as highlight the importance of having the REMC conductors away from the machine midplane in order to ensure they are robust to off-normal disruption scenarios. Submitted for publication in Nuclear Fusion

Constraints on ion velocity distributions from fusion product spectroscopy

2025-04-08T04:47:17Z

Constraints on ion velocity distributions from fusion product spectroscopy Crilly, A.J.; Appelbe, B.D.; Mannion, O.M.; Taitano, W.; Hartouni, E.P.; Moore, A.S.; Gatu Johnson, Maria; Chittenden, J.P. Recent inertial confinement fusion experiments have shown primary fusion spectral moments which are incompatible with a Maxwellian velocity distribution description. These results show that an ion kinetic description of the reacting ions is necessary. We develop a theoretical classification of non-Maxwellian ion velocity distributions using the spectral moments. At the mesoscopic level, a monoenergetic decomposition of the velocity distribution reveals there are constraints on the space of spectral moments accessible by isotropic distributions. General expressions for the directionally dependent spectral moments of anisotropic distributions are derived. At the macroscopic level, a distribution of fluid element velocities modifies the spectral moments in a constrained manner. Experimental observations can be compared to these constraints to identify the character and isotropy of the underlying reactant ion velocity distribution and determine if the plasma is hydrodynamic or kinetic. Submitted for publication in Nuclear Fusion

A simple screening current simulation method using equivalent circuit model for REBCO pancake coils

2025-04-08T04:10:59Z

A simple screening current simulation method using equivalent circuit model for REBCO pancake coils Noguchi, So; Imai, Teki; Park, Dongkeun; Hahn, Seungyong; Iwasa, Yukikazu The screening current induced in rare-earth barium copper oxide (REBCO) tape generates an unwanted irregular magnetic field. The screening current-induced field (SCIF) is a challenging issue for MRI, NMR, and accelerators magnet composed of REBCO coils. A few FEM-based simulation methods have been proposed to estimate the SCIF; however, they require a long computation time. Recently, we have proposed a simple SCIF computation method based on the self and mutual inductances of REBCO pancake coils and screening current radial paths on the top and bottom of pancake coils. The accuracy of the proposed method is not excellent; however, the computation time is quite short. In this paper, we report an equivalent circuit model that includes the self and mutual inductances of a REBCO pancake coil and screening current radial path. Moreover, with this proposed method, we can compute the SCIF of no-insulation (NI) REBCO pancake coils, which is not the case with the previously proposed FEM-based simulation method. The proposed method has been validated by experimentation. The proposed method is available online. Submitted for publication in Superconducting Science and Technology

Realization of thousand-second improved confinement plasma with Super I-mode in Tokamak EAST

2025-04-07T16:01:57Z

Realization of thousand-second improved confinement plasma with Super I-mode in Tokamak EAST Song, Yuntao; Zou, Xiaolan; Gong, Xianzu; Becoulet, Alain; Buttery, Richard; Bonoli, Paul T.; Hoang, Tuong; Zhong, Xiaoming; Liu, Adi; Li, Erzhong; Zang, Qing; Qian, Jinping; Liu, Haiqing; Wang, Liang; Xu, Liqing; Zhang, Ling; Li, Guoqiang; Garofalo, Andrea; Osborne, Tom; Leonard, Tony; Baek, Seung Gyou; Wallace, Greg M.; Wang, Shouxin; Chu, Yuqi; Zhang, Tao; Duan, Yanmin; Lian, Hui; Zhang, Xuexi; Jin, Yifei; Ding, Rui; Lyu, Bo; Zhang, Bin; Wang, Xiaojie; Ding, B.; Li, Miaohui; Zhang, Xinjun; Qing, Chengming; Xi, Weibin; Zhang, Jian; Huang, Liansheng; Yao, Damao; Hu, Yanlan; Zuo, Guizhong; Yuan, Qinping; Zhou, Zhiwei; Wang, Mao; Xu, Handong; Xie, Yahong; Wang, Zhengchu; Xu, Gupcheng; Hu, Jiansheng; Lu, Kun; Liu, Fukun; Wan, Baonian; Li, Jiangang; EAST Team Mastering nuclear fusion, which is an abundant, safe, and environmentally competitive energy, is a great challenge for humanity. Tokamak represents one of the most promising paths toward controlled fusion. Obtaining a high-performance, steady-state, and long-pulse plasma regime remains a critical issue. Recently, a big breakthrough in steady-state operation was made on the Experimental Advanced Superconducting Tokamak (EAST). A steady-state plasma with a world-record pulse length of 1056 s was obtained, where the density and the divertor peak heat flux were well controlled, with no core impurity accumulation, and a new high-confinement and self-organizing regime (Super I-mode = I-mode + e-ITB) was discovered and demonstrated. These achievements contribute to the integration of fusion plasma technology and physics, which is essential to operate nextstep devices. Submitted for publication in Science Advances

Proton imaging of high-energy-density laboratory plasmas

2025-04-07T09:18:21Z

Proton imaging of high-energy-density laboratory plasmas Schaeffer, D.B.; Bott, A.F.A.; Borghesi, M.; Flippo, K.A.; Fox, W.; Fuchs, J.; Li, Chi-Kang; Sénguin, Frederick H.; Park, H.-S.; Tzeferacos, P.; Willingale, L. Proton imaging has become a key diagnostic for measuring electromagnetic fields in high-energydensity (HED) laboratory plasmas. Compared to other techniques for diagnosing fields, proton imaging is a measurement that can simultaneously offer high spatial and temporal resolution and the ability to distinguish between electric and magnetic fields without the protons perturbing the plasma of interest. Consequently, proton imaging has been used in a wide range of HED experiments, from inertial-confinement fusion to laboratory astrophysics. An overview is provided on the state of the art of proton imaging, including a discussion of experimental considerations like proton sources and detectors, the theory of proton-imaging analysis, and a survey of experimental results demonstrating the breadth of applications. Topics at the frontiers of proton-imaging development are also described, along with an outlook on the future of the field. Submitted for publication in Reviews of Modern Physics

The Realization of a Gas Puff Imaging System on the Wendelstein 7-X Stellarator

2025-04-08T04:30:24Z

The Realization of a Gas Puff Imaging System on the Wendelstein 7-X Stellarator Terry, James L.; von Stechow, A.; Baek, Seung Gyou; Ballinger, S.B.; Grulke, O.; von Sehren, C.; Laube, R.; Killer, C.; Scharmer, F.; Brunner, K.J.; Knauer, J.; Bois, S.; W7-X Team A system for studying the spatio-temporal dynamics of fluctuations in the boundary of the W7-X plasma using the ``Gas-Puff Imaging'' (GPI) technique has been designed, constructed, installed, and operated. This GPI system addresses a number of challenges specific to long-pulse superconducting devices like W7-X, including the long distance between the plasma and the vacuum vessel wall, the long distance between the plasma and diagnostic ports, the range of last closed flux surface (LCFS) locations for different magnetic configurations in W7-X, and management of heat loads on the system's plasma-facing components. The system features a pair of ``converging-diverging'' nozzles for partially collimating the gas puffed locally approximately 110 mm radially outboard of the plasma boundary, a pop-up turning mirror for viewing the gas puff emission from the side (which also acts as a shutter for the re-entrant vacuum window), and a high-throughput optical system that collects visible emission resulting from the interaction between the puffed gas and the plasma and directs it along a water-cooled re-entrant tube directly onto the 8 x 16 pixel detector array of the fast camera. The DEGAS 2 neutrals code was used to simulate the H-alpha (656 nm) and the HeI (587 nm) line emission expected from well-characterized gas-puffs of H2 and He and excited within typical edge plasma profiles in W7-X, thereby predicting line brightnesses used to reduce the risks associated with system sensitivity and placement of the field of view. Operation of GPI on W7-X shows excellent signal to noise ratios (>100 at 2 Mframes/s) over the field of view for minimally perturbing gas puffs. The GPI system provides detailed measurements of the 2-dimensional (radial and poloidal) dynamics of plasma fluctuations in the W7-X edge and scrape-off layer, and in and around the magnetic islands outside the LCFS that make up the island divertor configuration employed on W7-X. Submitted for publication in Review of Scientific Instruments

Determining spectral response of the National Ignition Facility particle time of flight diagnostic to x rays

2025-04-08T04:26:00Z

Determining spectral response of the National Ignition Facility particle time of flight diagnostic to x rays Reichelt, Benjamin L.; Kabadi, Neel V.; Pearcy, Jacob A.; Gatu Johnson, Maria; Dannhoff, S.; Lahmann, Brandon; Frenje, Johan A.; Li, Chi-Kang; Sutcliffe, G.; Kunimune, Justin H.; Petrasso, Richard D.; Sio, H.; Moore, A.; Mariscal, E.; Hartouni, E. The Particle Time of Flight (PTOF) diagnostic is a chemical vapor deposition (CVD) diamond detector used for measuring multiple nuclear bang times at the National Ignition Facility (NIF). Due to the non-trivial, polycrystalline structure of these detectors, individual characterization and measurement is required to interrogate the sensitivity and behavior of charge carriers. In this paper, a process is developed for determining the xray sensitivity of PTOF detectors and relating it to intrinsic properties of the detector. We demonstrate that the diamond sample measured has a significant non-homogeneity in its properties, with the sensitivity given by a linear model $ax+b$, where $a=0.60 \pm 0.16 V^{-1}mm^{-1}$ and $b=0.00 \pm 0.04 V^{-1}$. We also use this method to confirm an electron to hole mobility ratio of $1.5 \pm 1.0$ and an effective band gap of $1.8 eV$ rather than the theoretical $5.5eV$, leading to a large sensitivity increase. Submitted for publication in Review of Scientific Instruments

A high-resolution neutron spectroscopic camera for the SPARC tokamak based on the JET European Torus Deuterium-Tritium experience

2025-04-07T08:31:43Z

A high-resolution neutron spectroscopic camera for the SPARC tokamak based on the JET European Torus Deuterium-Tritium experience Tardocchi, M.; Rebai, M.; Rigamonti, D.; Tinguely, R. Alex; Caruggi, F.; Croci, G.; Dal Molin, A.; Ghani, Z.; Giacomelli, L.; Girolami, M.; Grosso, G.; Kushoro, M.; Marcer, G.; Mastellone, M.; Muraro, A.; Nocente, M.; Perelli Cippo, E.; Petruzzo, M.; Putignano, O.; Scionti, J.; Serpente, V.; Trucchi, D.M.; Mackie, S.; Saltos, A.A.; De Marchi, E.; Parisi, M.; Trotta, A.; de la Luna, E.; Garcia, J.; Kazakov, Y.; Maslov, Mm.; Stancar, Z.; Gorini, G.; JET contributors Dedicated nuclear diagnostics have been designed, developed and built within EUROFUSION enhancement programs in the last ten years for installation at the Joint European Torus (JET) and capable of operation in high power Deuterium-Tritium (DT) plasmas. The recent DT Experiment campaign, called DTE2, has been successfully carried out in the second half of 2021 and provides a unique opportunity to evaluate the performance of the new nuclear diagnostics and for understanding of their behavior in the record high 14 MeV neutron yields (up to 4.7*10^18 n/s) and total number of neutrons (up to 2*10^19 n) achieved on a tokamak. In this work we will focus on the 14 MeV high resolution neutron spectrometers based on artificial diamonds which for the first time have extensively been used to measure 14 MeV DT neutron spectra with unprecedented energy resolution (FWHM of ~1% at 14 MeV). The work will describe their long-term stability and operation over the DTE2 campaign as well as their performance as neutron spectrometers in terms of achieved energy resolution and high rate capability. This important experience will be used to outline the concept of a spectroscopic neutron camera for the SPARC tokamak. The proposed neutron camera will be the first one to feature the dual capability to measure i) the 2.5 and 14 MeV neutron emissivity profile, via the conventional neutron detectors based on liquid or plastics scintillators, and ii) the 14 MeV neutron spectral emission via the use of high-resolution diamond-based spectrometers. The new opportunities opened by the spectroscopic neutron camera to measure plasma parameters will be discussed. Submitted for publication in Review of Scientific Instruments

Response of CR-39 nuclear track detectors to protons with non-normal incidence

2025-04-07T09:21:49Z

Response of CR-39 nuclear track detectors to protons with non-normal incidence Przybocki, Ryan; Gatu Johnson, Maria; Sutcliffe, G.; Lahmann, Brandon; Séguin, Frederick H.; Frenje, Johan A.; Adrian, Patrick J.; Johnson, Timothy M.; Pearcy, Jacob A.; Kabadi, Neel V.; Birkel, Andrew; Petrasso, Rirchard D. This paper presents data from experiments with protons at non-normal incidence to CR-39 nuclear track detectors, analyzing the properties of detection efficiency, proton track diameter, track contrast, and track eccentricity. Understanding the CR-39 response to protons incident at an angle is important for designing charged particle detectors for inertial confinement fusion (ICF) applications. This study considers protons with incident energies less than 3 MeV. In this regime, an incident angle of 10° has no effect on CR-39 detection efficiency, and >85% detection efficiency is preserved up through 25° in the range of 1.0 MeV–2.1 MeV. For ICF applications, incident angles above 30° are deemed impractical for detector design due to significant drops in proton detection at all energies. We observe significant reductions in detection efficiency compared to theoretical predictions, particularly at low energies where proton tracks are etched away. The proton track diameter measured by the scan system is observed to decrease with higher incident angles. The track diameters are analyzed with two fitting models, and it is shown that the diameter–energy relation can be fit with the existing models at angles up to 30°. The optical contrast of the tracks tends to increase with the angle, meaning that the tracks are fainter, and a larger increase is observed for higher energies. Eccentricity, a measure of how elongated proton tracks are, increases with the incident angle and drops after the critical angle. The lowest energy tracks remain nearly circular even at higher angles. Submitted for publication in Review of Scientific Instruments

EuroPED-NN: Uncertainty aware surrogate model

2025-04-07T09:21:42Z

EuroPED-NN: Uncertainty aware surrogate model Panera Alarez, A.; Ho, Aaron; Järvinen, A.; Saarelma, S.; Wiesen, S.; JET contributors; ASDEX Upgrade Team This work successfully generates an uncertainty-aware surrogate model of the EuroPED plasma pedestal model using the Bayesian neural network with noise contrastive prior (BNN-NCP) technique. This model is trained using data from the JET-ILW pedestal database and subsequent model evaluations, conforming to EuroPED-NN. The BNN-NCP technique has been proven to be a suitable method for generating uncertainty-aware surrogate models. It matches the output results of a regular neural network while providing confidence estimates for predictions as uncertainties. Additionally, it highlights out-of-distribution (OOD) regions using surrogate model uncertainties. This provides critical insights into model robustness and reliability. EuroPED-NN has been physically validated, first, analyzing electron density ne(ψ_pol = 0.94) with respect to increasing plasma current, Ip, and second, validating the Δ−β_p,ped relation associated with the EuroPED model. This affirms the robustness of the underlying physics learned by the surrogate model. On top of that, the method was used to develop a EuroPED-like model fed with experimental data, i.e. an uncertainty aware experimental model, which is functional in JET database. Both models have been also tested in ~50 AUG shots. Submitted for publication in Plasma Physics and Controlled Fusion

Design of the ion-optics for the MRSt neutron spectrometer at the National Ignition Facility (NIF)

2025-04-07T08:28:20Z

Design of the ion-optics for the MRSt neutron spectrometer at the National Ignition Facility (NIF) Berg, G.P.A.; Frenje, Johan A.; Kunimune, Justin H.; Trosseille, C.A.; Couder, M.; Kilkenny, J.D.; Mackinnon, A.J.; Moore, A.S.; Waltz, C.S.; Wiescher, M.C. A new Magnetic Recoil Spectrometer (MRSt) is designed to provide time-resolved measurements of the energy spectrum of neutrons emanating from an inertial confinement fusion implosion at the National Ignition Facility. At present, time integrated parameters are being measured using the existing magnet recoil and neutron time-of-flight spectrometers. The capability of high energy resolution of 2 keV and the extension to high time resolution of about 20 ps are expected to improve our understanding of conditions required for successful fusion experiments. The layout, ion-optics, and specifications of the MRSt will be presented. Submitted for publication in Review of Scientific Instruments

Top-level physics requirements and simulated performance of the MRSt on the National Ignition Facility

2025-04-07T08:51:49Z

Top-level physics requirements and simulated performance of the MRSt on the National Ignition Facility Kunimune, Justin H.; Frenje, Johan A.; Berg, G.P.A.; Trosseille, C.A.; Nora, R.C.; Waltz, C.S.; Moore, A.S.; Kilkenny, J.D.; Mackinnon, A.J. The time-resolving Magnetic Recoil Spectrometer (MRSt) for the National Ignition Facility (NIF) has been identified by the US National Diagnostic Working Group as one of the transformational diagnostics that will reshape the way inertial confinement fusion (ICF) implosions are diagnosed. The MRSt will measure the time-resolved neutron spectrum of an implosion, from which the time-resolved ion temperature, areal density, and yield will be inferred. Top-level physics requirements for the MRSt were determined based on simulations of numerous ICF implosions with varying degrees of alpha heating, P2 asymmetry, and mix. Synthetic MRSt data were subsequently generated for different configurations using Monte–Carlo methods to determine its performance in relation to the requirements. The system was found to meet most requirements at current neutron yields at the NIF. This work was supported by the DOE and LLNL. Submitted for publication in Review of Scientific Instruments

The Wendelstein 7-X phase contrast imaging diagnostic

2025-04-08T04:09:24Z

The Wendelstein 7-X phase contrast imaging diagnostic Huang, Zhouji; Edlund, E.; Porkolab, Miklos; von Stechow, A.; Bähner, J-P.; Böttger, L.-G.; v. Sehren, C.; Grulke, O. A phase contrast imaging (PCI) diagnostic has been developed for the Wendelstein 7-X (W7-X) stellarator. The PCI diagnostic provides line-integrated measurement of turbulent electron density fluctuations, which is essential for understanding and achieving high performance scenarios that can lead to improved confinement at fusion-relevant temperatures and densities. The PCI system is also sensitive to coherent fluctuations, which arise from Alfvén eigenmodes or other MHD activity. This paper provides an overview of the hardware and the optical system and presents an example of PCI measurement from the W7-X OP1.2b experimental campaign. Submitted for publication in Review of Scientific Instruments

The conceptual design of 1-ps time resolution neutron detector for fusion reaction history measurement at OMEGA and the National Ignition Facility

2025-04-07T08:49:59Z

The conceptual design of 1-ps time resolution neutron detector for fusion reaction history measurement at OMEGA and the National Ignition Facility Arikawa, Yasunobu; Ota, Masato; Nakajima, Makoto; Shimizu, Tomoki; Segawa, Sadashi; Phan, Thanh Nhat Khoa; Sakawa, Youichi; Abe, Yuki; Morace, Alessio; Mirfayzi, Seyed Reza; Yogo, Akifumi; Fujioka, Shinsuke; Nakai, Mitsuo; Shiraga, Hiroyuki; Azechi, Hiroshi; Kodama, Ryosuke; Kan, Koichi; Frenje, Johan A.; Gatu Johnson, Maria; Bose, Arijit; Kabadi, Neel V.; Sutcliffe, Graeme D.; Adrian, Patrick J.; Li, Chi-Kang; Séguin, Fredrick H.; Petrasso, Richard D. The nuclear burn history provides critical information about the dynamics of the hot-spot formation and high-density fuel-shell assembly of an Inertial Confinement Fusion (ICF) implosion, as well as information on the impact of alpha heating, and a multitude of implosion failure mechanisms. Having this information is critical for assessing the energy-confinement time τE and performance of an implosion. As the confinement time of an ICF implosion is a few tens of picoseconds, less than 10-ps time resolution is required for an accurate measurement of the nuclear burn history. In this study, we propose a novel 1-ps time-resolution detection scheme based on the Pockels effect. In particular, a conceptual design for the experiment on the National Ignition Facility and OMEGA are elaborated upon herein. A small organic Pockels crystal “DAST” is designed to be positioned ∼5 mm from the ICF implosion, which is scanned by a chirped pulse generated by a femtosecond laser transmitted through a polarization-maintained optical fiber. The originally linearly polarized laser is changed to an elliptically polarized laser by the Pockels crystal when exposed to neutrons, and the modulation of the polarization will be analyzed. Our study using 35-MeV electrons showed that the system impulse response is 0.6 ps. The response time is orders of magnitude shorter than current systems. Through measurements of the nuclear burn history with unprecedented time resolution, this system will help for a better understanding of the dynamics of the hot-spot formation, high-density fuel-shell assembly, and the physics of thermonuclear burn wave propagation. Submitted for publication in Review of Scientific Instruments

Novel SOLPS-ITER simulations of X-point target and snowflake divertors

2025-04-07T08:46:04Z

Novel SOLPS-ITER simulations of X-point target and snowflake divertors Cowley, C.; Kuang, Adam Q.; Moulton, D.; Lore, J.D.; Canik, J.; Umansky, M.; Wigram, Mike; Ballinger, S.; Lipschulz, B. The design and understanding of alternative divertor configurations may be crucial for achieving acceptable steady-state heat and particle material loads for magnetic confinement fusion reactors. Multiple X-point alternative divertor geometries such as snowflakes and X-point targets have great potential in reducing power loads, but have not yet been simulated widely in codes with kinetic neutrals. This paper discusses recent changes made to the SOLPS-ITER code to allow for the simulation of X-point target and low-field side snowflake divertor geometries. Snowflake simulations using this method are presented, in addition to the first SOLPS-ITER simulation of the X-point target. Analysis of these results show reasonable consistency with the simple modelling and theoretical predictions, supporting the validity of the methodology implemented. Submitted for publication in Plasma Physics and Controlled Fusion

Development of a synthetic phase contrast imaging diagnostic for turbulence studies at Wendelstein 7-X

2025-04-08T04:40:41Z

Development of a synthetic phase contrast imaging diagnostic for turbulence studies at Wendelstein 7-X Hansen, Soren K.; Porkolab, Miklos; Bähner, J.-P.; Huang, Z.; von Stechow, A.; Grulke, O.; Edlund, E.M.; Wilms, F.; Bañón Navarro, A.; Jenko, F.; Sánchez, E. We present a synthetic phase contrast imaging (PCI) diagnostic for studying turbulence at the Wendelstein 7-X (W7-X) stellarator. We first describe the implemented instrument response model, which captures diffraction effects, detector noise, and the long-wavelength cutoff due to the phase plate of the PCI system. To verify the instrument response model, we show that it is capable of reproducing the PCI signal generated by the sound wave speaker used for calibration at W7-X. Next, we discuss the calculation of synthetic PCI signals based on the global, nonlinear gyrokinetic codes GENE-3D and EUTERPE, including results from some of the first stellarator simulations of this type with kinetic electrons (KEs) in GENE-3D. While the simulations used in this work lack a neoclassical radial electric field, which is crucial for reproducing experimental PCI signals, they do indicate that the dominant rotation direction and velocities of the turbulent fluctuations can be inferred from the wave number-frequency spectra of the PCI signals, as expected. The synthetic PCI wave number spectra are further shown to be similar to those of the line-integrated fluctuating electron density, with distinct differences between adiabatic and KE simulations, explainable by previously published turbulence models. For example, the wave number spectra of all adiabatic electron simulations analyzed here follow a power law with an exponent close to −5 for sufficiently large wave numbers. This indicates that universal features of electron density turbulence at W7-X may be studied using the PCI system. Submitted for publication in Plasma Physics and Controlled Fusion

Effects of alpha-ion stopping on ignition and ignition criteria in inertial confinement fusion experiments

2025-04-07T09:22:52Z

Effects of alpha-ion stopping on ignition and ignition criteria in inertial confinement fusion experiments Reichelt, Benjamin L.; Petrasso, Richard D.; Li, Chi-Kang With the advent of ignited plasmas at the National Ignition Facility (NIF), alpha physics has become a driving factor in theoretical understanding and experimental behavior. In this communication, we explore aspects of direct alpha-ion heating through comparison of the consequences from the one-fluid and two-fluid models in the hydrodynamic approach. We show that the case with all alpha energy deposited in electrons raises the ignition criteria by ~4 keV or ~0.2 g/cm2 in the hotspot relative to the case with all alpha energy deposited in ions. In the case of the recently ignited NIF implosion, 30% of the 3.5 MeV a energy is deposited into the DT fuel ions, for which there is negligible difference between the one-fluid and two-fluid ignition criteria. However, changes in the ion stopping fraction through profile effects and alternate stopping power models could lead to ignition curve shifts of ~1 keV. Submitted for publication in Physics of Plasmas

Kinetic theory of parametric decay instabilities near the upper hybrid resonance in plasmas

2025-04-07T09:14:25Z

Kinetic theory of parametric decay instabilities near the upper hybrid resonance in plasmas Han, Jiangyue; Gao, Zhe; Hansen, Soren K. Parametric decay instabilities (PDIs) near the upper hybrid resonance layer are studied with a 1D framework. In a uniform plasma, the kinetic nonlinear dispersion relation of PDI is numerically calculated for parameters corresponding to electron cyclotron heating experiments at the ASDEX-U tokamak, in which O-mode radiation was converted to X-mode radiation by reflection from the high-field sidewall. The forward scattering processes driven by X-mode and linearly converted electron Bernstein waves (EBWs) are investigated and found to lead to a primary PDI where the pump waves decay into lower hybrid waves and sideband EBWs. A frequency shift of 930 MHz is obtained for the sideband EBWs in the primary PDIs. Subsequently, the sideband EBWs can decay into a low-frequency ion Bernstein quasi- mode (IBQM) and a secondary EBW, where the dominant forward scattering channel is the first-order IBQM with a frequency close to twice the ion cyclotron frequency. The decay channels obtained by numerical calculation can explain the characteristics of the signal observed in ASDEX-U experiments. The threshold of the pump electric field strength required to excite the primary PDI in the presence of plasma inhomogeneity is also estimated. Submitted for publication in Physics of Plasmas

Investigating Boosted Decision Trees as a Guide for Inertial Confinement Fusion Design

2025-04-07T09:20:39Z

Investigating Boosted Decision Trees as a Guide for Inertial Confinement Fusion Design Maris, Andrew D.; Khan, Shahab F.; Pokornik, Michael M.; Peterson, J. Luc; Humbird, Kelli D.; Haan, Steven W. Inertially confined fusion experiments at the National Ignition Facility have recently entered a new regimes apporaching ignition. Improved modelling and exploration of the experimental parameter space were essential to deepening our understanding of the mechanisms that degrade and amplify the neutron yield. The growing prevalence of machine learning in fusion studies opens a new avenue for investigation. In this paper, we have applied the Gradient Boosted Decision Tree (GBDT) machine learning architecture to further explore the parameter space and find correlations with the neutron yield, a key performance indicator. We find reasonable agreement between the measured and predicted yield, with a mean absolute percentage error on a randomly assigned test set of 35.5%. This model finds the characteristics of the laser pulse to be the most influential in prediction, as well as the hohlraum opening size and the new capsule fabrication technique. We used the trained model to scan over the design space of experiments from three different campaigns to evaluate the potential of this technique to provide design changes that could improve the resulting neutron yield. While this data-driven model cannot predict ignition without examples of ignited shots in the training set, it can be used to indicate that an unseen shot design will at least be in the upper range of previously observed neutron yields. Submitted for publication in Physics of Plasmas

Mitigation of mode-one asymmetry in laser-direct-drive inertial confinement fusion implosions

2025-04-07T08:26:37Z

Mitigation of mode-one asymmetry in laser-direct-drive inertial confinement fusion implosions Mannion, O.M.; Igumenshchev, I.V.; Anderson, K.S.; Betti, R.; Campbell, E.M.; Cao, D.; Forrest, C.J.; Gatu Johnson, Maria; Glebov, V.Yu.; Goncharov, V.N.; Gopalaswamy, V.; Ivancic, S.T.; Jacobs-Perkins, D.W.; Kalb, A.; Knauer, J.P.; Kwiatkowski, J.; Lees, A.; Marshall, F.J.; Michalko, M.; Mohamed, Z.L.; Patel, D.; Rinderknecht, H.G.; Shah, R.C.; Stoeckl, C.; Theobald, W.; Woo, K.M.; Regan, S.P. Nonuniformities present in the laser illumination and target in laser-driven inertial confi nement fusion experiments lead to an asymmetric compression of the target, resulting in an inefficient conversion of shell kinetic energy to thermal energy of the hot-spot plasma. In this paper, the effects of asymmetric compression of cryogenic deuterium tritium laser-direct-drive implosions are examined using a suite of nuclear and x-ray diagnostics on the OMEGA laser. The neutron-averaged hot-spot velocity (~uhs) and apparent ion temperature (Ti) asymmetry are determined from neutron time-of-flight measurements of the primary deuterium tritium fusion neutron energy spectrum, while the areal density (rhoR) of the compressed fuel surrounding the hot spot is inferred from measurements of the scattered neutron energy spectrum. The low-mode perturbations of the hot-spot shape are characterized from x-ray self-emission images recorded along three quasi-orthogonal lines of sight. Implosions with signifi cant mode-1 laser drive asymmetries show large hot-spot velocities (>100 km/s) in a direction consistent with the hot-spot elongation observed in x-ray images, measured Ti asymmetry, and rhoR asymmetry. Laser drive corrections have been applied through shifting the initial target location in order to mitigate the observed asymmetry. With the asymmetry corrected, a more-symmetric hot spot is observed with reduced ~uhs, Ti asymmetry, rhoR asymmetry, and a 30% increase in the fusion yield. Submitted for publication in Physics of Plasmas

Validation of IMEP on Alcator C-Mod and JET-ILW ELMy H-mode plasmas

2025-04-07T08:26:44Z

Validation of IMEP on Alcator C-Mod and JET-ILW ELMy H-mode plasmas Luda, T.; Angioni, C.; Dunne, M.G.; Fable, E.; Kallenbach, A.; Bonanomi, N.; Schneider, P.A.; Siccinio, M.; Tardini, G.; ASDEX Upgrade Team; EUROfusion MST1 Team; Rodriguez Fernandez, Pablo; Hughes, Jerry W.; Howard, Nathan T.; Alcator C-Mod Team; Frassinetti, L.; Saarelma, S.; JET contributors The recently developed integrated model based on engineering parameters (IMEP) (Luda et al 2020 Nucl. Fusion 61 126048; Luda et al 2021 Nucl. Fusion 60 036023), so far validated on ASDEX Upgrade, has been tested on a database of 3 Alcator C-Mod and 55 JET-ILW ELMy (type I) H-mode stationary phases. The empirical pedestal transport model included in IMEP, consisting now of imposing a fixed value of R < rTe > =Te;top = -82:5, allows an accurate prediction of the pedestal top temperature (when the pedestal top density is fixed to the experimental measurements) across these three machines with different sizes, when the pedestal is peeling–ballooning (PB) limited. Cases far from the ideal PB boundary, corresponding to high edge Spitzer resistivity, are instead strongly overpredicted by IMEP. A comparison between the predictions of Europed and IMEP for a subset of JET-ILW cases shows that IMEP can more accurately reproduce the experimental pedestal width. This allows IMEP to better capture profile effects on the pedestal stability, and therefore to correctly describe the negative effect of fueling on the pedestal pressure for PB limited cases. A strong correlation between the separatrix density and the fueling rate has been identified for a subset of JET-ILW cases, when taking into account different divertor configurations. Overall, these promising results encourage further developments of integrated models to obtain reliable predictions of pedestal and global confinement using only engineering parameters for present and future machines. Submitted for publication in Plasma Physics and Controlled Fusion

Diagnosing hot-spot symmetry in surrogate ignition experiments via secondary DT-neutron spectroscopy at the NIF

2025-04-07T08:26:42Z

Diagnosing hot-spot symmetry in surrogate ignition experiments via secondary DT-neutron spectroscopy at the NIF Adrian, Patrick J.; Bionta, R.; Casey, D.; Gatu Johnson, Maria; Kerr, S.; Lahmann, Brandon; Li, Chi-Kang; Nora, R.; Petrasso, Richard D.; Rigon, G.; Schlossberg, D.; Séguin, Frederick H.; Frenje, Johan A. The directional energy spectrum of neutrons generated from the in-flight fusion reaction of 1-MeV tritons contains information about the hot-spot symmetry. The National Ignition Facility (NIF) fields Symmetry Capsule (Symcap) implosions, which have historically measured the symmetry of the radiation, drive by measuring the hot-spot shape via x-ray self-emission. Symcaps are used to tune the hot-spot symmetry for ignition experiments at the NIF. This work shows the relationship between directional secondary DT-n spectra and x-ray imaging data for a large database of Symcap implosions. A correlation is observed between the relative widths of the DT-n spectra measured with nTOFs and the shape measured with x-ray imaging. A Monte Carlo model, which computes the directional secondary DT-n spectrum, is used to interpret the results. A comparison of the x-ray and secondary DT-n data with the Monte Carlo model indicates that 56% of the variance between the two datasets is explained by a P2 asymmetry. More advanced simulations using HYDRA suggest that the unaccounted variance is due to P1 and P4 asymmetries present in the hot spot. The comparison of secondary DT-n data and x-ray imaging data to the modeling shows the DT-n data contain important information that supplements current P2 measurements and contain new information about the P1 asymmetry. Submitted for publication in Physics of Plasmas

Further Rotation Reversal Studies in C-Mod L-mode Plasmas

2025-04-08T04:51:38Z

Further Rotation Reversal Studies in C-Mod L-mode Plasmas Rice, John E.; Cao, N.M.; Diamond, P.H.; Greenwald, M.J.; Hubbard, Amanda E.; Marmar, E.S.; Reinke, M.L.; Rodriguez-Fernandez, P. Studies of core toroidal rotation reversal phenomenology in C-Mod deuterium L-mode plasmas have been expanded to include details of the dependences on plasma current and toroidal magnetic field. Rotation reversal occurs at a critical density and universal scaling indicates that the product of n_crit q_95 R ~ B_T/2, with n_crit in 10^20/m^3, R in m and B_T in T. Measurements in H and He plasmas exhibit similar behavior, including a connexion with the LOC/SOC transition and the cut-off for non-diffusive heat transport. Electron density and ICRF power modulation experiments suggest that the collisionality nu_* is a unifying parameter. Strong impurity puffing causes the critical density to increase, indicating that the situation is more complicated than only collisionality, perhaps involving the details of the effects of dilution on ITG mode stability. Submitted for publication in Physics of Plasmas

Measurements of improved stability to achieve higher fuel compression in ICF

2025-04-07T09:16:01Z

Measurements of improved stability to achieve higher fuel compression in ICF Do, A.; Casey, D.T.; Clark, D.S.; Bachman, B.; Baker, K.L.; Braun, T.; Briggs, T.M.; Chapman, T.D.; Celliers, P.M.; Chen, H.; Choate, C.; Dewald, E.L.; Divol, L.; Fathi, G.; Fittinghoff, D.N.; Hall, G.N.; Hartouni, E.; Holunga, D.M.; Khan, S.F.; Kritcher, A.L.; Landen, O.L.; MacPhee, A.G.; Millot, M.; Marley, E.V.; Milovich, J.L.; Nikroo, A.; Pak, A.E.; Schlossberg, D.J.; Smalyuk, V.A.; Stadermann, M.; Strozzi, D.J.; Tommasini, R.; Weber, C.R.; Woodworth, B.N.; Yanagisawa, D.K.; Birge, N.W.; Danly, C.R.; Durocher, M.; Freeman, M.S.; Geppert-Kleinrath, H.; Geppert-Kleinrath, V.; Kim, Y.; Meaney, K.D.; Wilde, C.H.; Gatu Johnson, Maria; Allen, A.; Ratledge, M.; Kong, C.; Fehrenbach, T.; Wild, C. While nuclear fusion ignition has been achieved at the National Ignition Facility (NIF) in inertial confinement fusion (ICF) experiments, obtaining higher gain and more efficient burn is still desired. In that regard, increasing the compression of the fuel is an important factor. In recent indirect-drive capsule implosions, the SQ-n campaign is testing the hypothesis that reducing the hydrodynamic growth of perturbations is key to achieving higher compression of high-density carbon (HDC) based-ablators for ICF. SQ-n uses a design at lower adiabat with a ramped foot laser pulse shape to minimize early-time hydrodynamic instability growth, predicted to be reduced by a factor of 10, and an optimized ablator dopant distribution. Subsets of experiments were conducted within the SQ-n campaign to study the implosion symmetry, laser backscatter, stability, and compression. Only the latter two will be reviewed here. Shock timing experiments using the VISAR diagnostic enabled the development of a gently accelerating shock velocity. The ice-ablator interface acceleration, important for managing the Richtmyer-Meshkov phase growth, was observed with refraction enhanced radiography (RER) and the ablation front growth was measured using radiography of pre-imposed modulations. Finally, layered THD and DT implosions demonstrate that between 15%+/-3% and 30%+/-6% improved compression has been achieved. Submitted for publication in Physics of Plasmas

Experimental Study of the Edge Radial Electric Field in Different Drift Configurations and its Role in the Access to H-mode at ASDEX Upgrade

2025-04-08T04:31:07Z

Experimental Study of the Edge Radial Electric Field in Different Drift Configurations and its Role in the Access to H-mode at ASDEX Upgrade Plank, U.; Brida, D.; Conway, G.D.; Happel, T.; Hubbard, Amanda E.; Pütterich, T.; Angioni, C.; Cavedon, M.; Dux, R.; Eich, T.; Fischer, R.; Hennequin, P.; ASDEX Upgrade Tea, The formation of the equilibrium radial electric field (Er) has been studied experimentally at ASDEX Upgrade (AUG) in L-modes of ’favourable’ (ion ∇B-drift towards primary X-point) and ’unfavourable’ (ion ∇B-drift away from primary X-point) drift configuration, in view of its impact on H-mode access, which changes with drift configuration. Edge electron and ion kinetic profiles, impurity velocity and mean-field Er profiles across the separatrix are investigated, employing new and improved measurement techniques. The experimental results are compared to local neoclassical theory as well as to a simple 1D scrape-off layer (SOL) model. It is found that in L-modes of matched heating power and plasma density the upstream SOL Er and the main ion pressure gradient in the plasma edge are the same for either drift configuration, whereas the Er well in the confined plasma is shallower in unfavourable compared to favourable drift configuration. The contributions of toroidal and poloidal main ion flows to Er, which are inferred from local neoclassical theory and the experiment, cannot account for these observed differences. Furthermore, it is found that in L-mode the intrinsic toroidal edge rotation decreases with increasing collisionality and it is co-current in the bananaplateau regime for all different drift configurations at AUG. This gives rise to a possible interaction of parallel Pfirsch-Schlüter flows in the SOL with the confined plasma. Thus, the different H-mode power threshold for the two drift configurations can not be explained in the same way at AUG as suggested by LaBombard et al. for Alcator C-Mod1. Finally, comparisons of Er profiles in favourable and unfavourable drift configuration at the respective confinement transitions show that also there the Er gradients are all different, which indirectly indicates a different type or strength of the characteristic edge turbulence in the two drift configurations. Submitted for publication in Physics of Plasmas

Inferences of hot electron preheat and its spatial distribution in OMEGA direct drive implosions

2025-04-08T04:48:18Z

Inferences of hot electron preheat and its spatial distribution in OMEGA direct drive implosions Christopherson, A.R.; Betti, R.; Forrest, C.J.; Howard, J.; Theobald, W.; Campbell, E.M.; Delettrez, J.; Rosenberg, M.J.; Solodov, A.; Stoeckl, C.; Patel, D.; Gopalaswamy, V,; Cao, D.; Peebles, J.; Edgell, D.; Seka, W.; Epstein, R.; Scullin, W.; Radha, P.B.; Wei, M.S.; Regan, S.P.; Gatu Johnson, Maria; Simpson, R. Hot electrons generated from laser plasma instabilities degrade performance of direct drive implosions by preheating the deuterium and tritium (DT) fuel resulting in early decompression and lower areal densities at stagnation. A technique to quantify the hot electron preheat of the dense DT fuel and connect it to the degradation in areal density is described in detail. Hot electrons are measured primarily from the hard x-rays they emit as they slow down in the target. The DT preheat is inferred from a comparison of the hard x-ray signals between a DT-layered implosion and its mass equivalent ablator only implosion. The preheat energy spatial distribution within the imploding shell is inferred from experiments using high Z payloads of varying thicknesses. It is found that the electrons deposit their energy uniformly throughout the shell material. For typical direct-drive OMEGA implosions driven with an overlapped intensity of ∼9·10^14 W/cm2, approximately ∼0.02%–0.03% of the laser energy is converted into preheat of the stagnated fuel which corresponds to areal density degradations of 10%–20%. The degradations in areal density explain some of the observed discrepancies between the simulated and measured areal densities. Submitted for publication in Physics of Plasmas

Modeling hydrodynamics, magnetic fields and synthetic radiographs for high-energy-density plasma flows in shock-shear targets

2025-04-07T08:36:51Z

Modeling hydrodynamics, magnetic fields and synthetic radiographs for high-energy-density plasma flows in shock-shear targets Lu, Yingchoa; Li, Shengtai; Li, Hui; Flippo, Kirk A.; Barnak, Dan; Birkel, Andrew; Lahmann, Brandon; Li, Chi-Kang; Rasmus, Alexander M.; Kelso, Kwyntero; Zylstra, Alex; Liang, Edison; Tzeferacos, Petros; Lamb, Don Three-dimensional FLASH radiation-magnetohydrodynamics (radiation-MHD) modeling is carried out to study the hydrodynamics and magnetic fields in the shock-shear derived platform. Simulations indicate that fields of tens of Tesla can be generated via Biermann battery effect due to vortices and mix in the counter-propagating shock-induced shear layer. Synthetic proton radiography simulations using MPRAD and synthetic X-ray image simulations using SPECT3D are carried out to predict the observable features in the diagnostics. Quantifying the effects of magnetic fields in inertial confinement fusion (ICF) and high-energy-density (HED) plasmas represents frontier research that has far-reaching implications in basic and applied sciences. Submitted for publication in Physics of Plasmas

Edge turbulence measurements in L-mode and I-mode at ASDEX Upgrade

2025-04-08T04:13:52Z

Edge turbulence measurements in L-mode and I-mode at ASDEX Upgrade Bielajew, R.; Conway, G.D.; Griener, M.; Happel, T.; Höfler, K.; Howard, Nathan T.; Hubbard, Amanda E.; McCarthy, William; Molina Cabrera, Pedro A.; Nishizawa, T.; Rodriguez-Fernandez, P.; Silvagni, D.; Vanovac, B.; Wendler, D.; Yoo, C.; White, Anne E.; The ASDEX Upgrade Team The I-mode confinement regime is promising for future reactor operation due to high energy confinement without high particle confinement. However, the role of edge turbulence in creating I-mode's beneficial transport properties is still unknown. New measurements of edge turbulence in L-modes and I-modes at low and high densities at ASDEX Upgrade are presented in this paper. A high radial resolution correlation electron cyclotron emission radiometer measures the broadband turbulence throughout the L-mode and I-mode edge and pedestal. The weakly coherent mode (WCM) is measured in both L-mode and I-mode near the last closed flux surface with Te fluctuation levels of 2.3%–4.2%, with a frequency shift between the two phases related to a deeper Er well in I-mode. An nT phase diagnostic captures a change of the WCM nT phase between L-mode and I-mode. The thermal He beam diagnostic measures a WCM wavenumber range of −0.5 to −1.0 cm−1. A low-frequency edge oscillation (LFEO) appears in the I-mode phase of these discharges and displays coupling to the WCM, but the LFEO does not appear in the L-mode phase. Linear gyrokinetic simulations of the outer core and pedestal top turbulence indicate that while the dominant turbulent modes in the outer core are ion directed and electrostatic, the turbulence becomes increasingly electron directed and electromagnetic with increasing radius. Collisionality is not found to impact characteristics of the L-mode and I-mode edge turbulence with respect to the presence of the WCM; however, the quality of global confinement decreases with collisionality. Submitted for publication in Physics of Plasmas

Scaling of laser-driven electron and proton acceleration as a function of laser pulse duration, energy, and intensity in the multi-picosecond regime

2025-04-07T08:24:46Z

Scaling of laser-driven electron and proton acceleration as a function of laser pulse duration, energy, and intensity in the multi-picosecond regime Simpson, R.A.; Scott, G.G.; Mariscal, D.; Rusby, D.; King, P.M.; Grace, E.; Aghedo, A.; Pagano, I.; Sinclair, M.; Armstrong, C.; Manuel, M. J.-E.; Haid, A.; Flippo, K.; Winslow, L.; Gatu Johnson, Maria; Frenje, Johan A.; Neely, D.; Kerr, S.; Williams, G.J.; Andrews, S.; Cauble, R.; Charron, K.; Costa, R.; Fischer, B.; Maricle, S.; Stuart, B.; Albert, F.; Lemos, N.; Mackinnon, A.; MacPhee, A.; Pak, A.; Ma, T. A scaling study of short-pulse laser-driven proton and electron acceleration was conducted as a function of pulse duration, laser energy, and laser intensity in the multi-picosecond (ps) regime (∼0.8 ps–20 ps). Maximum proton energies significantly greater than established scaling laws were observed, consistent with observations at other multi-ps laser facilities. In addition, maximum proton energies and electron temperatures in this regime were found to be strongly dependent on the laser pulse duration and preplasma conditions. A modified proton scaling model is presented that is able to better represent the accelerated proton characteristics in this multi-ps regime. Submitted for publication in Physics of Plasmas

Effects of F3+ ion implantation on the properties of W and W0.5(TaTiVCr)0.5 for depth marker-based plasma erosion analysis

2025-04-08T04:20:05Z

Effects of F3+ ion implantation on the properties of W and W0.5(TaTiVCr)0.5 for depth marker-based plasma erosion analysis Waseem, Owais Ahmed; Woller, Kevin Benjamin; Sweidan, Faris Bassam; JinRyu, Ho The irradiation resistance of tungsten (W) and a high-entropy alloy-based material W0.5(TaTiVCr)0.5 was analysed using depth marker implantation (F3+ ions irradiation). Mirror-polished W and W0.5(TaTiVCr)0.5 samples were exposed to 5.0 MeV and 4.2 MeV, respectively, F3+ ions up to a maximum fluence of 3.2x1012 ions/cm2. The scanning electron and atomic force microscopy of implanted W showed nanostructure and pinholes, respectively, whereas the surface of implanted W0.5(TaTiVCr)0.5 remained fairly smooth. The nanoindentation hardness of W and W0.5(TaTiVCr)0.5 increased from 6.6 GPa to 8.5 GPa and from 13.9 GPa to 16.3 GPa, respectively, due to implantation. The ion implantation induced lattice defects and compressive stress, as a result, the BCC peaks of W and W0.5(TaTiVCr)0.5 moved to higher Bragg angles. The irradiation induced strain in W0.5(TaTiVCr)0.5 (4.4x10-4) remained lower than that in pure W (8.5x10-4). The comparison of W and W0.5(TaTiVCr)0.5 suggested the higher resistance of W0.5(TaTiVCr)0.5 to high energy ion implantation. Submitted for publication in Nuclear Materials and Energy

Summary of the IAEA technical meeting on plasma disruptions and their mitigation

2025-04-08T04:34:17Z

Summary of the IAEA technical meeting on plasma disruptions and their mitigation Bandyopadhyay, Indranil; Barbarino, Matteo; Bhattacharjee, Amitava; Eidietis, Nicholas; Huber, Alexander; Isayama, Akihiko; Kim, Jayhyun; Konovalov, Sergey; Lehnen, Michael; Nardon, Eric; Pautasso, Gabriella; Rea, Cristina; Sozzi, Carlo; Villone, Fabio; Zeng, Long This report summarizes the contributions presented at the IAEA technical meeting on plasma disruptions and their mitigation, held virtually, 20–23 July 2020. The meeting brought together more than 120 experts from nuclear fusion research sites worldwide to discuss experimental, theoretical and modelling work in the field of plasma disruptions with special emphasis on developing a solid basis for possible disruption mitigation strategies in ITER and next generation fusion devices. The main topics of the meeting were: (i) disruption consequences, including electromagnetic loads, heat loads, and runaway electrons; (ii) disruption prediction and avoidance, including machine learning and physics-based approaches, and control aspects; and (iii) disruption mitigation, including shattered pellet injection, alternative techniques and general aspects of disruption mitigation. Submitted for publication in Nuclear Fusion

Scoping study of lower hybrid current drive for CFETR

2025-04-07T09:08:50Z

Scoping study of lower hybrid current drive for CFETR Wallace, Greg M.; Ding, B.J.; Li, M.H.; Chen, J.; Baek, Seung Gyou; Bonoli, Paul T.; Shiraiwa, S.; Liu, L.; Wu, C.B. The paper assesses the applicability of lower hybrid current drive (LHCD) for two potential operating scenarios for the China Fusion Engineering Test Reactor (CFETR): the “hybrid” scenario in which some of the plasma current is sustained by the Ohmic transformer, and the fully non-inductive “steady state” scenario. The πScope workflow engine was used to set up a large number of ray tracing/Fokker- Planck simulations (> 10^4) with parametric scans in the antenna poloidal position and launched parallel refractive index (n||) for both the hybrid and steady state scenarios. Modeling predicts efficient off-axis current drive (1.3 MA for 20 MW launched power) with a peak near ρ of 0.6-0.65 for waves launched from the high field side (HFS). Waves launched from the low field side (LFS) damp at larger radius (ρ > 0.73) with similar efficiency to HFS launch. Stability analysis of the CFETR scenarios favors current drive profiles peaked near the mid-radius, suggesting that HFS launch is preferable due to the current drive location. The effect of wave scattering from density blobs in the edge/scrape-off-layer region was assessed through rotation of the perpendicular wavenumber at the ray origin. Simulations show that this effect can be quite large both in efficiency and damping location, however by adjusting the launched n|| much of the unperturbed performance can be recovered. Submitted for publication in Nuclear Fusion

Hybrid deep learning architecture for general disruption prediction across tokamaks

2025-04-07T09:16:23Z

Hybrid deep learning architecture for general disruption prediction across tokamaks Zhu, Jinxiang; Rea, Cristina; Montes, Kevin J.; Granetz, R.S.; Sweeney, Ryan; Tinguely, R. Alex In this paper, we present a new deep learning disruption prediction algorithm based on important findings from explorative data analysis which effectively allows knowledge transfer from existing devices to new ones, thereby predicting disruptions using very limited disruptive data from the new devices. The explorative data analysis conducted via unsupervised clustering techniques confirms that time-sequence data are much better separators of disruptive and non-disruptive behavior than the instantaneous plasma state data with further advantageous implications for a sequence-based predictor. Based on such important findings, we have designed a new algorithm for multi-machine disruption prediction that achieves high predictive accuracy on the C-Mod (AUC=0.801), DIII-D (AUC=0.947) and EAST (AUC=0.973). tokamaks with limited hyperparameter tuning. Through numerical experiments, we show that boosted accuracy (AUC=0.959) is achieved on EAST predictions by including in the training only 20 disruptive discharges, thousands of non-disruptive discharges from EAST, and combining this with more than a thousand discharges from DIII-D and C-Mod. The improvement of predictive ability obtained by combining disruptive data from other devices is found to be true for all permutations of the three devices. Furthermore, by comparing the predictive performance of each individual numerical experiment, we find that non-disruptive data are machine-specific while disruptive data from multiple devices contain device-independent knowledge that can be used to inform predictions for disruptions occurring on a new device. Submitted for publication in Nuclear Fusion

On the very high energy confinement observed in super H-mode DIII-D experiments

2025-04-07T09:06:51Z

On the very high energy confinement observed in super H-mode DIII-D experiments Ding, S.; Garofalo, A.M.; Knolker, M.; Marinoni, Alessandro; McClenaghan, J.; Grierson, B.A. Analysis of recent super H-mode experiments on DIII-D shows that high rotation, not high pedestal, plays the essential role in achieving very high conﬁnement H98y2 > 1.5. Very high conﬁnement is reached early on in the H-mode phase of these discharges, when the pedestal is still very low, but after the toroidal rotation has already built-up to very high levels in the core. As the discharge evolves, the rotation drops, and so does the energy conﬁnement, despite a sustained very high pressure pedestal. During this evolution, the conﬁnement quality is linearly correlated with the core toroidal rotation, which varies according to diﬀerent levels of injected neutral beam torque per particle. Core transport modeling shows that the contribution from rotation in the E×B shear is responsible for conﬁnement quality signiﬁcantly in excess of standard H-mode (H98y2 ∼ 1). Submitted for publication in Nuclear Fusion

Neoclassical transport in strong gradient regions of large aspect ratio tokamaks

2025-04-08T04:19:39Z

Neoclassical transport in strong gradient regions of large aspect ratio tokamaks Trinczek, Silvia; Parra, Felix I.; Catto, Peter J.; Calvo, Iván; Landreman, Matt We present a new neoclassical transport model for large aspect ratio tokamaks where the gradient scale lengths are of the size of the poloidal gyroradius. Previous work on neoclassical transport across transport barriers assumed large density and potential gradients but a small temperature gradient, or neglected the gradient of the mean parallel flow. Using large aspect ratio and low collisionality expansions, we relax these restrictive assumptions. We define a new set of variables based on conserved quantities, which simplifies the drift kinetic equation whilst keeping strong gradients, and derive equations describing the transport of particles, parallel momentum and energy by ions in the banana regime. The poloidally varying parts of density and electric potential are included. Studying contributions from both passing and trapped particles, we show that the resulting transport is dominated by trapped particles. We find that a non-zero neoclassical particle flux requires parallel momentum input which could be provided through interaction with turbulence or impurities. We derive upper and lower bounds for the energy flux across a transport barrier in both temperature and density and present example profiles and fluxes. Submitted for publication in Journal of Plasma Physics

Reimagining full wave rf quasilinear theory in a tokamak

2025-04-07T08:27:33Z

Reimagining full wave rf quasilinear theory in a tokamak Catto, Peter J.; Tolman, Elizabeth A. The velocity dependent resonant interaction of particles with applied radio frequency (rf) waves during heating and current drive in the presence of pitch angle scattering collisions gives rise to narrow collisional velocity space boundary layers that dramatically enhance the role of collisions as recently shown by Catto (J. Plasma Phys., vol. 86, 815860302, 2020). The behavior is a generalization of the narrow collisional boundary layer that forms during Landau damping as found by Johnston (Phys. Fluids, vol. 14, 1971, pp. 2719-2726) and Auerbach (Phys. Fluids, vol. 20, 1977, pp. 1836-1844). For a wave of parallel wave number k|| interacting with weakly collisional plasma species of collision frequency ν and thermal speed vth , the effective collision frequency becomes of order ν(k_||v_th /ν)^2/3>> ν . The narrow boundary layers that arise because of the diffusive nature of the collisions allows a physically meaningful wave-particle interaction time to be defined that is the inverse of this effective collision frequency. The collisionality implied by the narrow boundary layer results in changes in the standard quasilinear treatment of applied rf fields in tokamaks while remaining consistent with causality. These changes occur because successive poloidal interactions with the rf are correlated in tokamak geometry and because the resonant velocity space dependent interactions are controlled by the spatial and temporal behavior of the perturbed full wave fields rather than just the spatially local Landau and Doppler shifted cyclotron wave-particle resonance condition associated with unperturbed motion of the particles. The correlation of successive poloidal circuits of the tokamak leads to the appearance in the quasilinear operator of transit averaged resonance conditions localized in velocity space boundary layers that maintain negative definite entropy production. Submitted for publication in Journal of Plasma Physics

Contamination of Argon X-ray Spectra by Tungsten and Other Elements Commonly Found in Tokamaks

2025-04-07T09:02:49Z

Contamination of Argon X-ray Spectra by Tungsten and Other Elements Commonly Found in Tokamaks Rice, John E.; Gu, M.; Cao, N.M.; Hughes, Jerry W.; Reinke, M.L.; Sertoli, M.; Vezinet, D. Emission lines which appear in the spectral ranges of ground state transitions from n = 2 levels in He- and H-like argon ions are discussed. X-ray transitions from elements commonly found in tokamaks (tungsten, molybdenum, iron and sulphur) which radiate in the wavelength range from 3700 - 4000 mA are identified by comparison with atomic structure calculations. Individual lines from tungsten charge states in the vicinity of Zn-like W^44+ are documented, along with B-like Mo^37+. The behavior of line ratios as a function of electron temperature is examined, in support of the identifications. Submitted for publication in Journal of Physics B: Atomic, Molecular and Optical Physics

Qubit Lattice Algorithms Based on the Schrodinger-Dirac Representation of Maxwell Equations and Their Extensions

2025-04-07T09:18:57Z

Qubit Lattice Algorithms Based on the Schrodinger-Dirac Representation of Maxwell Equations and Their Extensions Vahala, George; Soe, Min; Kououtsis, Efstratios; Hizanidis, Kyriakos; Vahala, Linda; Ram, Abhay K. It is well known that Maxwell equations can be expressed in a unitary Schrodinger-Dirac representation for homogeneous media. However, difficulties arise when considering inhomogeneous media. A Dyson map points to a unitary field qubit basis, but the standard qubit lattice algorithm of interleaved unitary collision-stream operators must be augmented by some sparse non-unitary potential operators that recover the derivatives on the refractive indices. The effect of the steepness of these derivatives on two-dimensional scattering is examined with simulations showing quite complex wavefronts emitted due to transmissions/reflections within the dielectric objects. Maxwell equations are extended to handle dissipation using Kraus operators. Then, our theoretical algorithms are extended to these open quantum systems. A quantum circuit diagram is presented as well as estimates on the required number of quantum gates for implementation on a quantum computer. Submitted for publication in IntechOpen

First-Cut Design of a Benchtop Cryogen-Free 23.5-T/25-mm Magnet for 1-GHz Microcoil NMR

2025-04-07T08:26:04Z

First-Cut Design of a Benchtop Cryogen-Free 23.5-T/25-mm Magnet for 1-GHz Microcoil NMR Park, Dongkeun; Dong, Fangliang; Lee, Wooseung; Bascuñán, Juan; Iwasa, Yukikazu As a preliminary work, we have completed a 12.5-mm-cold-bore high-temperature superconducting (HTS) REBCO magnet prototype and successfully operated it up to 25 T at 10 K cooled by a cryocooler only, without liquid helium. In this paper we present the first-cut design of a cryogen-free all-REBCO 23.5-T/25-mm-warm-bore magnet having a high homogeneity of <0.1 ppm over a 1-cm diameter of spherical volume for a benchtop 1-GHz microcoil NMR spectroscopy. We also investigate a shielding design to reduce a 5-gauss fringe field radius to ≤1.5 m. This benchtop magnet will incorporate all the innovative design and operation concepts validated by the prototype magnet: 1) all-HTS composition and operation at above 4.2 K; 2) no-insulation winding technique with an extra shunting that makes this high-field REBCO magnet compact, mechanically robust, and self-protecting; 3) a single coil formation that leads, compared with the traditional multi- nested high-field NMR magnet, to simpler and more affordable manufacturing processes; 4) operational temperature-controlled screening-current reduction method which reduces peak stresses within the REBCO coil and field errors; and 5) cryogenic design for conduction-cooling operation. Submitted for publication in IEEE Transactions on Applied Superconductivity

An MgB2 Superconducting Joint with its own Heat-Treatment Schedule

2025-04-08T04:18:33Z

An MgB2 Superconducting Joint with its own Heat-Treatment Schedule Tanaka, Hiromi; Li, Yi; Choi, Yoonhyuck; Park, Dongkeun; Lee, Wooseung; Tanaka, Hideki; Bascuñán, Juan; Iwasa, Yukikazu We suggested an MgB2 joint process with its own heat-treatment schedule to apply it for our 1.5-T MgB2 “finger” MRI magnet. In fabricating the MgB2 magnet, the optimal heat-treatment schedule to attain a reproducible and high critical current is different in a joint and a coil. To solve this problem, we introduced an additional heating system, which is composed of a cartridge heater and a thermocouple connected with a copper block, into a box-type furnace. Then, we carried out heattreatments with exclusively increasing the joint-part temperature above theMgmelting point of 645 °C—the jointwas actually heated up to 700 °C.We evaluated a critical current and a crystal structure of the obtained MgB2 joint. From experimental results, we found that the joint heated with the own heat-treatment schedule, which is 700 °C for 1 h+600°C for 11 h, showed a good Ic of over 450 A at 15K under self-field. The joint resistance was estimated by the coil operation for 18 days, and it was expected to be less than 10−12 Ω. Submitted for publication in IEEE Transactions on Applied Superconductivity

Overview of the Neutron Diagnostic Systems for the SPARC Tokamak

2025-04-08T04:50:30Z

Overview of the Neutron Diagnostic Systems for the SPARC Tokamak Raj, P.; Ball, J.L.; Carmichael, J.; Frenje, Johan A.; Gocht, R.; Gorini, G.; Holmes, I.; Gatu Johnson, Maria; Kennedy, R.; Mackie, S.; Noncente, M.; Panontin, E.; Petruzzo, M.; Rebai, M.; Reinke, M.; Rice, John E.; Rigamonti, D.; Dalla Rosa, M.; Saltos, A.A.; Tardocchi, M.; Tinguely, R. Alex; Wang, X. Neutron measurement is the primary tool in the SPARC tokamak for fusion power (Pfus) monitoring, research on the physics of burning plasmas, validation of the neutronics simulation workflows, and providing feedback for machine protection. A demanding target uncertainty (10% for Pfus) and coverage of a wide dynamic range (>8 orders of magnitude going up to 5x10^19 n/s), coupled with a fast-track timeline for design and deployment, make the development of the SPARC neutron diagnostics challenging. Four subsystems are under design, which exploit the high flux of direct DT and DD plasma neutrons emanating from a shielded opening in a midplane diagnostic port. The systems comprise: a set of ~15 flux monitors mainly ionization chamber and proportional counters for measurement of the neutron yield rate, two independent foil activation systems for measurement of the neutron fluence, a spectrometric radial neutron camera for poloidal profiling of the plasma emissivity, and a high-resolution magnetic proton recoil spectrometer for measurement of the core neutron spectrum. Together, the four systems ensure redundancy of sensors and methods, and aim to provide high resolutions of time (10 ms), space (~7 cm), and energy (<2% at 14 MeV). This paper presents the broader objectives behind the preliminary design of the SPARC neutron diagnostics, and discusses the ongoing studies on neutronics, detector comparisons, prototyping, and integration with the unique infrastructure of SPARC. Engineering details of the four subsystems and the concepts for in-situ neutron calibration are also highlighted. Submitted for publication in Review of Scientific Instruments

Quantification and visualization of uncertainties in reconstructed penumbral images of implosions at Omega

2025-04-07T09:14:46Z

Quantification and visualization of uncertainties in reconstructed penumbral images of implosions at Omega Kunimune, Justin H.; Heuer, P.V.; Reichelt, Benjamin L.; Johnson, Timothy M.; Frenje, Johan A. Penumbral imaging is a technique used in plasma diagnostics in which a radiation source shines through one or more large apertures onto a detector. To interpret a penumbral image, one must reconstruct it to recover the original source. The inferred source always has some error due to noise in the image and uncertainty in the instrument geometry. Interpreting the inferred source thus requires quantification of that inference’s uncertainty. Markov chain Monte Carlo algorithms have been used to quantify uncertainty for similar problems but have never been used for the inference of the shape of an image. Because of this, there are no commonly accepted ways of visualizing uncertainty in two- dimensional data. This paper demonstrates the application of the Hamiltonian Monte Carlo algorithm to the reconstruction of penumbral images of fusion implosions and presents ways to visualize the uncertainty in the reconstructed source. This methodology enables more rigorous analysis of penumbral images than has been done in the past. Submitted for publication in Review of Scientific Instruments

The next-generation Magnetic Recoil Spectrometer (MRSnext) on OMEGA and NIF for diagnosing ion temperature, yield, areal density, and alpha heating

2025-04-07T09:12:45Z

The next-generation Magnetic Recoil Spectrometer (MRSnext) on OMEGA and NIF for diagnosing ion temperature, yield, areal density, and alpha heating Wink, Christopher W.; Gatu Johnson, Maria; Mackie, S.; Kunimune, Justin H.; Dannhoff, S.G.; Lawrence, Y.; Berg, G.P.A.; Casey, D.T.; Schlossberg, D.J.; Gopalaswamy, V.; Katz, J.; Regan, S.P.; Stoeckl, C.; Burgett, T.; Ivancic, S.; McClow, H.; Scott, M.; Frelier, J.; Frenje, Johan A. The next-generation magnetic recoil spectrometer (MRSnext) is being designed to replace the current MRS at the National Ignition Facility and OMEGA for measurements of the neutron spectrum from an inertial confinement fusion implosion. The MRSnext will provide a far-superior performance and faster data turnaround than the current MRS systems, i.e., a 2× and 6× improvement in energy resolution at the NIF and OMEGA, respectively, and 20× improvement in data turnaround time. The substantially improved performance of the MRSnext is enabled by using electromagnets that provide a short focal plane (12–16 cm) and unprecedented flexibility for a wide range of applications. In addition to being able to measure neutron yield, apparent ion temperature, areal density, and plasma-flow velocity over a wide range of yields, the NIF MRSnext will be able to directly, uniquely assess the alpha heating of the fuel ions through measurements of the alpha knock-on tail in the neutron spectrum. The goal is to implement a radiation-hard electronic detection system capable of providing rapid data acquisition and analysis. The development of the MRSnext will also set the foundation for the more advanced, time-resolving MRSt and serve as a testbed for its implementation on the NIF. Submitted for publication in Review of Scientific Instruments

Aligning the Thomson scattering and charge exchange recombination diagnostics using neutral beam emission at DIII-D

2025-04-08T04:21:47Z

Aligning the Thomson scattering and charge exchange recombination diagnostics using neutral beam emission at DIII-D Feyrer, Abigail; Haskey, S.R.; Chrystal, C.; Aidala, C.A. This work addresses discrepancies in the alignment of the H-mode pedestal profiles of the electron and ion properties in the DIII-D tokamak as measured by Thomson Scattering (TS) and Charge Exchange Recombination Spectroscopy (CER) diagnostics. While the alignment of these profiles is key for accurate studies of tokamak physics and plasma confinement, misalignments can occur due to inaccuracies, such as in magnetic equilibrium reconstructions required to map measurements in different poloidal and toroidal locations. Both FIDASIM, an established simulation package, and a simplified collisional radiative model are used to simulate neutral beam state densities and neutral beam emission. Simulated neutral beam emissions are calculated based on shifted TS profiles and compared to beam emission measurements from the Main Ion CER system to determine the best shift for aligning TS with CER. This analysis is performed on various DIII-D discharges. Submitted for publication in Review of Scientific Instruments

Robust Identification of Multiple Input Single Output System Response for Efficient Pickup Noise Removal from Tokamak Diagnostics

2025-04-07T09:06:19Z

Robust Identification of Multiple Input Single Output System Response for Efficient Pickup Noise Removal from Tokamak Diagnostics Odstrcil, T.; Laggner, F.; Rosenthal, Aaron M.; Bortolon, A.; Hughes, Jerry W.; Spendlove, J.C.; Wilks, Theresa M. Electromagnetic pickup noise in the tokamak environment imposes an imminent challenge for measuring weak diagnostic photocurrents nA range. The diagnostic signal can be contaminated by an unknown mixture of crosstalk signals from coils powered by currents in kA range. To address this issue, an algorithm for robust identification of linear multi-input single-output (MISO) systems has been developed. MISO model describes the dynamic relationship between measured signals from power sources and observed signals in the diagnostics and allows for a precise subtraction of the noise component. The proposed method was tested on experimental diagnostic data from the DIII-D tokamak, and it has reduced noise by up to 20 dB in 1–20 kHz range. Submitted for publication in Review of Scientific Instruments

High-yield magnetic recoil neutron spectrometer on the National Ignition Facility for operation up to 60 MJ

2025-04-07T09:10:51Z

High-yield magnetic recoil neutron spectrometer on the National Ignition Facility for operation up to 60 MJ Gatu Johnson, Maria; Johnson, Timothy M.; Lahmann, Brandon; Séguin, Frederick H.; Sperry, B.; Bhandarkar, N.; Bionta, R.M.; Casco, E.; Casey, D.T.; Mackinnon, A.J.; Masters, N.; Moore, A.; Nikroo, A.; Hoppe, M.; Mohammed, R.; Sweet, W.; Freeman, C.; Picciotto, V.; Roumell, J.; Frenhe, Johan A. Recent progress at the National Ignition Facility (NIF), with neutron yields of order 1 × 10^17, places new constraints on diagnostics used to characterize implosion performance. The Magnetic Recoil neutron Spectrometer (MRS), which is routinely used to measure yield, ion temperature (Tion), and down-scatter ratio (dsr), has been adapted to allow measurements of dsr up to 5 × 10^17, and yield and Tion up to 2 × 10^18 in the near term with new data processing techniques and conversion foil solutions. This paper presents a solution for extending MRS operation up to a yield of 2 × 10^19 (60 MJ) by moving the spectrometer outside of the NIF shield wall. This will not only enhance the upper yield limit by 10× but also improve signal-to-background by 5×. Submitted for publication in Review of Scientific Instruments

Absolute calibration of the Lyman- α measurement apparatus at DIII-D

2025-04-07T09:15:06Z

Absolute calibration of the Lyman- α measurement apparatus at DIII-D Laggner, F.M.; Bortolon, A.; Rosenthal, Aaron M.; Wilks, Theresa M.; Hughes, Jerry W.; Freeman, C.; Golfinopoulos, T.; Nagy, A.; Mauzey, D.; Shafer, M.W.; DIII-D Team The LLAMA (Lyman-Alpha Measurement Apparatus) diagnostic was recently installed on the DIII-D tokamak [Rosenthal et al., Rev. Sci. Instrum. (submitted) (2020)]. LLAMA is a pinhole camera system with a narrow band Bragg mirror, a bandpass interference filter, and an absolute extreme ultraviolet photodiode detector array, which measures the Ly-α brightness in the toroidal direction on the inboard, high field side (HFS) and outboard, low field side (LFS). This contribution presents a setup and a procedure for an absolute calibration near the Ly-α line at 121.6 nm. The LLAMA in-vacuum components are designed as a compact, transferable setup that can be mounted in an ex situ vacuum enclosure that is equipped with an absolutely calibrated Ly-α source. The spectral purity and stability of the Ly-α source are characterized using a vacuum ultraviolet spectrometer, while the Ly-α source brightness is measured by a NIST-calibrated photodiode. The non-uniform nature of the Ly-α source emission was overcome by performing a calibration procedure that scans the Ly-α source position and employs a numerical optimization to determine the emission pattern. Nominal and measured calibration factors are determined and compared, showing agreement within their uncertainties. A first conversion of the measured signal obtained from DIII-D indicates that the Ly-α brightness on the HFS and LFS is on the order of 1020 Ph sr^{−1} m^{−2} s^{−1}. The established calibration setup and procedure will be regularly used to re-calibrate the LLAMA during DIII-D vents to monitor possible degradation of optical components and detectors. Submitted for publication in Review of Scientific Instruments

Diagnostic development for parallel wave-number measurement of lower hybrid waves in EAST

2025-04-07T09:23:50Z

Diagnostic development for parallel wave-number measurement of lower hybrid waves in EAST Wang, Y.F.; Ding,B.J.; Li, M.H.; Baek, Seung Gyou; Wallace, Greg M.; Liu, L.; Zhao, L.M.; Wang, M.; Wu, Z.G.; Liu, F.K.; Shan, J.F.; Zhang, X.J.; Li, Y.C.; Wu, C.B. An eight-channel magnetic probe diagnostic system has been designed and installed adjacent to the 4.6 GHz lower hybrid (LH) grill antenna in the low-field side of the EAST tokamak in order to study the n|| evolution of lower hybrid waves in the first pass from the launcher to the core plasma. The magnetic probes are separated by 6.6 mm, which allows measurement of the dominant parallel refractive index n|| up to n|| =5 for 4.6GHz LH waves. The magnetic probes are designed to be sensitive to the magnetic field component perpendicular to the background magnetic field with a slit on the casing that encloses the probe. The intermediate frequency (IF) stage, which consists of two mixing stages, down-coverts the frequency of the measured wave signals at 4.6 GHz to 20 MHz. A bench test demonstrates the phase stability of the magnetic probe diagnostic system. By evaluating the phase variation of the measured signals along the background magnetic field, the dominant n|| of the LH wave in the scrape-off layer (SOL) has been deduced during the 2019 experimental campaign. In the low density plasma, the measured dominant n|| of the lower hybrid waves is about 2.1, corresponding to the main peak 2.04 of the launched n|| spectrum. The n|| deduced by the least square linear fit method remains near this value in the low density plasma with a high spatial correlation magnitude of 0.9. With an eight-channel probe system a wave-number spectrum has also been deduced, which has a peak near to the measured dominant n||. Submitted for publication in Review of Scientific Instruments

Influence of Proton Irradiation on Corrosion in Liquid Lead

2025-04-08T04:42:58Z

Influence of Proton Irradiation on Corrosion in Liquid Lead Zhou, Weiyue; Cairang, Wande; Amadeo, Paola; Woller, Kevin B.; Short, Michael P. The next-generation Gen IV nuclear reactors are designed to operate under increasingly challenging environments, aiming for higher thermal efficiency while adhering to strict physical and safety constraints. These harsh conditions, characterized by elevated temperatures and accelerated corrosion rates, coupled with the presence of high radiation damage rates, necessitate a thorough understanding of the complex interaction between radiation and corrosion. However, experiments that incorporate radiation into the corrosion evaluation of structural materials, particularly in liquid metal environments, are scarce and challenging to conduct. To address this research gap, we have developed a unique experimental apparatus that enables simultaneous irradiation and corrosion testing using proton beams as the radiation source. In this setup, a foil sample is exposed to liquid lead on one side, while protons are directed from the opposite side, resulting in a central region within the foil that experiences both irradiation and liquid lead corrosion. By comparing the behavior of this central region with the surrounding areas, we can observe the specific effects introduced by the additional proton beam on the corrosion process. This facility provides valuable insights into the rates and mechanisms of radiation-altered corrosion in lead and lead-bismuth eutectic (LBE) environments, ultimately contributing to improved material selection, design optimization, and enhanced corrosion resistance in nextgeneration reactor systems. Submitted for publication in Transactions of the American Nuclear Society

Persistent-mode operation and magnetization behavior of a solid-nitrogen-cooled MgB2small-scale test coil towards a tabletop 1.5-T osteoporosis MRI

2025-04-07T08:39:18Z

Persistent-mode operation and magnetization behavior of a solid-nitrogen-cooled MgB2small-scale test coil towards a tabletop 1.5-T osteoporosis MRI Choi, Yoonhyuck; Park, Dongkeun; Li, Yi; Tanaka, Hiromi; Lee, Wooseung; Bascuñan, Juan; Iwasa, Yukikazu We present results—cooldown, energization, and persistent-mode operation—of a solid nitrogen (SN2)-cooled, magnesium diboride (MgB2) small-scale test coil. The test coil, immersed in a volume of solid nitrogen at 6 K, successfully operated in persistent-mode at 108 A for a period of 5 days. Although designated a “persistent-mode” coil, its center field was measured to decay at a rate of < 0.6 ppm·h-1, which is still considered low enough to meet the temporal stability requirement for most magnetic resonance imaging magnets. This decay rate translates to a calculated circuit resistance of < 1.79 × 10-12 Ω, which is mainly from one MgB2-MgB2 joint in the circuit. However, when the coil temperature increased from 6 to 16 K, the field had dropped by 0.33%: we believe this was caused by the change of magnetization in the MgB2 superconductor, which in turn decreased a screening-current field (SCF) at the magnet center. We performed a finite element analysis with a simplified numerical model based on H formulation to verify whether magnetization-induced SCF is responsible for this 0.33% drop. Indeed, the model shows that the change of magnetization, i.e., screening current reduction and current density redistribution, happens during temperature-cycle-induced Jc(T) variation, and thus affects the center magnetic field. However, the Jc(T) variation in the 2nd cycle had little effect on MgB2 magnetization and thus had negligible magnetic field change. Submitted for publication in Superconducting Science and Technology

Prototype REBCO Z1 and Z2 shim coils for ultra high‑fieldhigh‑temperature superconducting NMR magnets

2025-04-07T08:56:38Z

Prototype REBCO Z1 and Z2 shim coils for ultra high‑fieldhigh‑temperature superconducting NMR magnets Park, Dongkeun; Lee, Jiho; Bascuñán, Juan; Li, Zhuyong; Iwasa, Yukikazu We present promising results of novel high‑temperature superconducting (HTS) shim coil prototypes that circumvent the size and strength limitation of our earlier innovative HTS shim concept based on 46‑mm wide REBCO tape. The HTS shim coil is placed inside the HTS magnet, mainly for ultrahigh‑field (> 1 GHz or 23.5 T) NMR magnets, and thus unaffected from the windings’ diamagnetic wall effects. One full‑scale version will be applied to clean up Z1 and Z2 harmonic errors in the MIT 1.3‑ GHz high‑resolution NMR magnet composed of an 835‑MHz HTS insert, while another version for an MIT 1‑GHz microcoil NMR magnet whose small‑scale model we are currently building. The prototype sets were wound with a 2‑pile, 1.03‑mm wide, 0.30‑mm thick REBCO conductor. Operated at 77 K, the Z1 shim set generated a 1st harmonic field strength of 179 kHz/cm at 70 A, while the Z2 shim set, composed of two pairs, Z21 and Z22, generated the 2nd harmonic field of 141 kHz/cm2 at 50 A. Together with discussion on technical challenges for this REBCO shim coil concept, we demonstrate its feasibility for the next generation of ultra‑high‑field (UHF) HTS NMR magnets. Submitted for publication in Scientific Reports

3D reconstruction of an inertial-confinement fusion implosion with neural networks using multiple heterogeneous data sources

2025-04-07T08:25:54Z

3D reconstruction of an inertial-confinement fusion implosion with neural networks using multiple heterogeneous data sources Kunimune, Justin H.; Casey, D.T.; Kustowski, B.; Geppert-Kleinrath, V.; Divol, L.; Fittinghoff, D.N.; Volegov, P.L.; Kruse, M.K.G.; Gaffney, J.A.; Nora, R.C.; Frenje, Johan A. 3D asymmetries are major degradation mechanisms in inertial-confinement fusion implosions at the National Ignition Facility (NIF). These asymmetries can be diagnosed and reconstructed with the neutron imaging system (NIS) on three lines of sight around the NIF target chamber. Conventional tomographic reconstructions are used to reconstruct the 3D morphology of the implosion using NIS [Volegov et al., J. Appl. Phys. 127, 083301 (2020)], but the problem is ill-posed with only three imaging lines of sight. Asymmetries can also be diagnosed with the real-time neutron activation diagnostics (RTNAD) and the neutron time-of-flight (nToF) suite. Since the NIS, RTNAD, and nToF each sample a different part of the implosion using different physical principles, we propose that it is possible to overcome the limitations of too few imaging lines of sight by performing 3D reconstructions that combine information from all three heterogeneous data sources. This work presents a new machine learning-based reconstruction technique to do just this. By using a simple physics model and group of neural networks to map 3D morphologies to data, this technique can easily account for data of multiple different types. A simple proof-of-principle is presented, demonstrating that this technique can accurately reconstruct a hot-spot shape using synthetic primary neutron images and a hot-spot velocity vector. In particular, the hot-spot’s asymmetry, quantified as spherical harmonic coefficients, is reconstructed to within ±4% of the radius in 90% of test cases. In the future, this technique will be applied to actual NIS, RTNAD, and nToF data to better understand 3D asymmetries at the NIF. Submitted for publication in Review of Scientific Instruments

Particle transport constraints via Bayesian spectral fitting of multiple atomic lines

2025-04-07T08:59:09Z

Particle transport constraints via Bayesian spectral fitting of multiple atomic lines Sciortino, Francesco; Cao, N.M.; Howard, Nathan T.; Marmar, E.S.; Rice, John E. Optimized operation of fusion devices demands detailed understanding of plasma transport, a problem that must be addressed with advances in both measurement and data analysis techniques. In this work, we adopt Bayesian inference methods to determine experimental particle transport, leveraging opportunities from high-resolution He-like ion spectra in a tokamak plasma. The Bayesian spectral fitting code is used to analyze resonance (w), forbidden (z), intercombination (x, y), and satellite (k, j) lines of He-like Ca following laser blow-off injections on Alcator C-Mod. This offers powerful transport constraints since these lines depend differently on electron temperature and density, but also differ in their relation to Li-like, He-like, and H-like ion densities, often the dominant Ca charge states over most of the C-Mod plasma radius. Using synthetic diagnostics based on the AURORA package, we demonstrate improved effectiveness of impurity transport inferences when spectroscopic data from a progressively larger number of lines are included. Submitted for publication in Review of Scientific Instruments

Reconstructing 3-D Asymmetries in Laser-Direct-Drive Implosions on OMEGA

2025-04-07T08:34:36Z

Reconstructing 3-D Asymmetries in Laser-Direct-Drive Implosions on OMEGA Mannion, O.M.; Woo, K.M.; Crilly, A.J.; Forrest, C.J.; Frenje, Johan A.; Glebov, V.Yu.; Gatu Johnson, Maria; Knauer, J. P.; Mohamed, Z.L.; Romanofsky, M.H.; Stoeckl, C.; Theobald, W.; Regan, S.P. Three-dimensional reconstruction algorithms have been developed which determine the hot-spot velocity, hot-spot apparent ion temperature distribution, and fuel areal-density distribution present in laser-direct- drive inertial confinement fusion implosions on the OMEGA laser. These reconstructions rely on multiple independent measurements of the neutron energy spectrum emitted from the fusing plasma. Measurements of the neutron energy spectrum on OMEGA are made using a suite of quasi-orthogonal neutron time-of-flight detectors and a magnetic recoil spectrometer. These spectrometers are positioned strategically around the OMEGA target chamber to provide unique 3-D measurements of the conditions of the fusing hot spot and compressed fuel near peak compression. The uncertainties involved in these 3-D reconstructions are discussed and are used to identify a new nTOF diagnostic line of sight which when built will reduce the uncertainty in the hot-spot apparent ion temperature distribution from 700 to <400 eV. Submitted for publication in Review of Scientific Instruments

Saturn-ring proton backlighters for the NIF

2025-04-07T08:49:53Z

Saturn-ring proton backlighters for the NIF Zylstra, A.B.; Craxton, R.S.; Rygg, J.R.; Li, Chi-Kang; Carlson, L.; Manuel, M. J.-E.; Youngblood, K.; Garcia, E.M.; Browning, L.T.; Le Pape, S.; Candeias Lemos, N.; Lahmann, Brandon; Gatu Johnson, Maria Proton radiography is a well-established technique for measuring electromagnetic ﬁelds in high-energy-density plasmas. Fusion reactions producing monoenergetic particles, such as D3He, are commonly used as a source, produced by a capsule implosion. Using smaller capsules for radiography applications is advantageous as the source size decreases, but on the NIF this is complicated by the risk introduced from increasing blow-by light, since the phase plate focal spot size is much larger than the capsules. We report a demonstration of backlighter targets where a ‘Saturn’ ring is placed around the capsule to block this light. The nuclear performance of the backlighters is unperturbed by the addition of a ring. We also test a ring with an equatorial cutout, which severely aﬀects the proton emission and is not viable for radiography applications. These results demonstrate the general viability of Saturn ring backlighter targets for use on NIF. Submitted for publication in Review of Scientific Instruments

Disruption prediction on EAST tokamak using a deep learning algorithm

2025-04-07T09:13:58Z

Disruption prediction on EAST tokamak using a deep learning algorithm Guo, B.H.; Shen, B.; Chen, D.L.; Rea, Cristina; Granetz, R.S.; Huang, Y.; Zeng, L.; Zhang, H.; Qian, J.P.; Sun, Y.W.; Xiao, B.J. In this study, a long short-term memory (LSTM) model is trained on a large disruption warning database to predict the disruption on EAST tokomak. To compare the performance of the proposed model with the previously reported full convolutional neural network (CNN) (Guo et al 2020 Plasma Phys. Control. Fusion 63 025008), the same data set and diagnostic signals are used. Based on the test set, the area under the receiver operating characteristic curve, i.e. the AUC value of the LSTM model is obtained as 0.87, and the true positive rate (TPR) is sim87.5%, while the false positive rate (FPR) is sim15.1%. Since the LSTM model is more sensitive to radiation fluctuations than CNN, the prediction performance of LSTM model is inferior to that of CNN model (for CNN, AUC sim 0.92, TPR sim 87.5%, FPR sim 6.1%). However, the advance warning time of LSTM model is 14 ms earlier than that of CNN. To reduce the FPR and improve the performance of the model, more fast bolometer channels are added as the input signals of the LSTM model, including the radiation from the upper and lower edges and the plasma core. Consequently, for the same test set, the AUC value increases to 0.89, and the FPR decreases to sim9.4%, but the TPR also decreases to sim83.9%. In addition, the sensitivity of the model to radiation fluctuations caused by impurity behavior decreases significantly, and the warning time becomes 8.7 ms earlier as compared to that of the original model. Overall, it is proved that deep learning algorithms exhibit immense application potential in the disruption prediction of long-pulse fusion devices. Submitted for publication in Plasma Physics and Controlled Fusion

Results from the Alfven Eigenmode Active Diagnostic during the 2019-2020 JET deuterium campaign

2025-04-07T09:15:19Z

Results from the Alfven Eigenmode Active Diagnostic during the 2019-2020 JET deuterium campaign Tinguely, R. Alex; Puglia, P.G.; Fil, N.; Dowson, S.; Porkolab, Miklos; Fasoli, A.; Testa, D.; JET Contributors This paper presents results of extensive analysis of mode excitation observed during the operation of the Alfven Eigenmode Active Diagnostic (AEAD) in the JET tokamak during the 2019-2020 deuterium campaign. Six of eight toroidally spaced antennas, each with independent power and phasing, were successful in actively exciting stable MHD modes in 479 plasmas. In total, 4768 magnetic resonances were detected with up to fourteen fast magnetic probes. In this work, we present the calculations of resonant frequencies f0, damping rates \gamma < 0, and toroidal mode numbers n, spanning the parameter range f0 = 30 - 250 kHz, -\gamma = 0 - 13 kHz, and |n| < 30. In general, good agreement is seen between the resonant and the calculated toroidal Alfven Eigenmode frequencies, and between the toroidal mode numbers applied by the AEAD and estimated of the excited resonances. We note several trends in the database: the probability of resonance detection decreases with plasma current and external heating power; the normalized damping rate increases with edge safety factor but decreases with external heating. These results provide key information to prepare future experimental campaigns and to better understand the physics of excitation and damping of Alfven Eigenmodes in the presence of alpha particles during the upcoming DT campaign, thereby extrapolating with confidence to future tokamaks. Submitted for publication in Plasma Physics and Controlled Fusion

First large capsule implosions in a frustum-shaped hohlraum

2025-04-07T08:28:38Z

First large capsule implosions in a frustum-shaped hohlraum Baker, K.L.; Amendt, P.A.; Ross, J.S.; Smalyuk, V.A.; Landen, O.L.; Ho, D.D.; Khan, S.; Haan, S.W.; Lindl, J.D.; Mariscal, D.; Milovich, J.L.; MacLaren, S.; Ping, Y.; Strozzi, D.J.; Bionta, R.M.; Casey, D.T.; Celliers, P.M.; Fittinghoff, D.N.; Geppert-Kleinrath, H.; Geppert-Kleinrath, V.; Hahn, K.D.; Gatu Johnson, Maria; Kim, Y.; Meaney, K.; Millot, M.; Nora, R.; Volegov, P.L.; Wilde, C.H. We report on the first indirect-drive implosions driven by a dual conical frustum-shaped hohlraum denoted “frustraum” and the experimental tuning campaigns leading up to two layered implosions. The campaign utilized 1.2 mm and 1.4 mm inner radius HDC capsules and represented the largest HDC capsules to be imploded on the National Ignition Facility via indirect drive. Several techniques were successfully implemented to control the mode 2 symmetry of the implosions including changing the wall angle of the frustraum which is not possible with cylindrical hohlraums. A mode 4 feature was observed and its implications for hot spot mix discussed. Two layered implosions were conducted with 1.2 mm inner radius capsules, the latter of which achieved the highest layered capsule absorbed energy on the NIF using only 1.74 MJ of laser energy. The layered implosion results suggest that increasing capsule absorbed energy by itself is insufficient, and that further reducing coast time (time between end of laser pulse and bang time) to the 1 ns level is warranted to improve areal density, hot spot temperature and alpha heating and yield amplification. Submitted for publication in Physics of Plasmas

First Implementation of Gyrokinetic Exact Linearized Landau Collision Operator and Comparison with Models

2025-04-07T09:16:09Z

First Implementation of Gyrokinetic Exact Linearized Landau Collision Operator and Comparison with Models Pan, Qingjiang; Ernst, Darin R.; Crandall, Paul Gyrokinetic simulations are fundamental to understanding and predicting turbulent transport in magnetically confined fusion plasmas. Previous simulations have used model collision operators with approximate field-particle terms of unknown accuracy and/or have neglected collisional finite Larmor radius (FLR) effects. We have implemented the linearized Fokker–Planck collision operator with exact field-particle terms and full FLR effects in a gyrokinetic code (GENE). The new operator, referred to as “exact” in this paper, allows the accuracy of model collision operators to be assessed. The conservative Landau form is implemented because its symmetry underlies the conservation laws and the H-theorem, and enables numerical methods to preserve this conservation, independent of resolution. The implementation utilizes the finite-volume method recently employed to discretize the Sugama collision model in GENE, allowing direct comparison between the two operators. Results show the Sugama model appears accurate for the growth rates of trapped electron modes (TEMs) driven only by density gradients, but appreciably underestimates the growth rates as the collisionality and electron temperature gradient increase. The TEM turbulent fluxes near the nonlinear threshold using the exact operator are similar to the Sugama model for the eta_e=0 case, but substantially larger than the Sugama model for the eta_e=1 case. The FLR effects reduce the growth rates increasingly with wavenumber, deepening a “valley” at the intermediate binormal wavenumber as the unstable mode extends from the TEM regime to the electron temperature gradient (ETG) instability regime. Application to the Hinton–Rosenbluth problem shows zonal flows decay faster as the radial wavenumber increases and the exact operator yields weaker decay rates. Submitted for publication in Physics of Plasmas

Impact of stalk on directly-driven inertial confinement fusion implosions

2025-04-07T08:50:32Z

Impact of stalk on directly-driven inertial confinement fusion implosions Gatu Johnson, Maria; Adrian, Patrick J.; Anderson, K.S.; Appelbe, B.D.; Chittenden, J.P.; Crilly, A.J.; Edgell, D.; Forrest, C.J.; Frenje, Johan A.; Glebov, V.Yu.; Haines, B.M.; Igumenshchev, I.; Jacobs-Perkins, D.; Janezic, R.; Kabadi, Neel V.; Knauer, J.P.; Lahmann, Brandon; Mannion, O.M.; Marshall, F.J.; Michel, T.; Séguin, Frederick H.; Shah, R.; Stoeckl, C.; Walsh, C.A.; Petrasso, Richard D. Low-mode asymmetries have emerged as one of the primary challenges to achieving high-performing inertial confinement fusion (ICF) implosions. In direct-drive ICF, an important potential seed of such asymmetries is the capsule stalk mount, the impact of which has remained a contentious question. In this paper, we describe results from an experiment on the OMEGA laser with intentional offsets at varying angle to the capsule stalk mount, which clearly demonstrate the impact of the stalk mount on implosion dynamics. The angle between stalk and offset is found to significantly impact observables. Specifically, a larger directional flow is observed in neutron spectrum measurements when the offset is towards than away from the stalk, while an offset at 42deg to the stalk gives minimal directional flow but still generates a large flow field in the implosion. No significant directional flow is seen due to stalk only. Time-integrated x-ray images support these flow observations. A trend is also seen in implosion yield, with lower yield obtained for offsets with smaller angle than with larger angle towards the stalk. Radiation hydrodynamics simulations using 2D DRACO and 2D/3D Chimera not including the stalk mount and using 2D xRAGE including the stalk mount are brought to bear on the data. The yield trend, the minimal directional flow with stalk only, and the larger flow enhancement observed with the offset towards the stalk are all reproduced in the xRAGE simulations. The results strongly indicate that the stalk impact must be considered and mitigated to achieve high-performing implosions. Submitted for publication in Physics of Plasmas

2H(p, gamma) 3He cross section measurement using high-energy-density plasmas

2025-04-08T04:48:16Z

2H(p, gamma) 3He cross section measurement using high-energy-density plasmas Zylstra, A.B.; Herrmann, H.W.; Kim, Y.H.; McEvoy, A.; Frenje, Johan A.; Gatu Johnson, Maria; Petrasso, Richard D.; Glebov, V.Yu.; Forrest, C.; Delettrez, J.; Gales, S.; Rubery, M. An absolute cross section for the radiative capture reaction 2H(p, γ ) 3He has been measured at the OMEGA laser facility using inertially confined plasmas. These high-temperature plasmas are created by imploding a fuel containing capsule using laser ablation, and are advantageous in that they better mimic astrophysical systems. We measure an S factor for this reaction of 0.429 ± 0.026stat ± 0.072sys eV b at Ec.m. = 16.35 ± 0.40 keV, which is higher than the adopted evaluations. This reaction is important as a source of nuclear energy in protostars and brown dwarfs. It is also a critical reaction during big-bang nucleosynthesis, and an accurate cross section can be used as a constraint on cosmology. Submitted for publication in Physical Review. C, Nuclear physics

Effect of Strongly Magnetized Electrons and Ions on Heat Flow and Symmetry of Inertial Fusion Implosions

2025-04-07T08:48:54Z

Effect of Strongly Magnetized Electrons and Ions on Heat Flow and Symmetry of Inertial Fusion Implosions Bose, A.; Peebles, J.; Walsh, C.A.; Frenje, Johan A.; Kabadi, Neel V.; Adrian, Patrick J.; Sutcliffe, G.D.; Gatu Johnson, Maria; Frank, C.A.; Davies, J.R.; Betti, R.; Glebov, V.Yu.; Marshall, F.J.; Regan, S.P.; Stoeckl, C.; Campbell, E.M.; Sio, H.; Moody, J.; Crilly, A.; Appelbe, B.D.; Chittenden, J.P.; Atzeni, S.; Barbato, F.; Forte, A.; Li, Chi-Kang; Séguin, Frederick H.; Petrasso, Richard D. This Letter presents the first observation on how a strong, 500 kG, externally applied B field increases the mode-two asymmetry in shock-heated inertial fusion implosions. Using a direct-drive implosion with polar illumination and imposed field, we observed that magnetization produces a significant increase in the implosion oblateness (a 2.5× larger P2 amplitude in x-ray self-emission images) compared with reference experiments with identical drive but with no field applied. The implosions produce strongly magnetized electrons (ωeτe ≫ 1) and ions (ωiτi > 1) that, as shown using simulations, restrict the cross field heat flow necessary for lateral distribution of the laser and shock heating from the implosion pole to the waist, causing the enhanced mode-two shape. Submitted for publication in Physical Review Letters

Observation of Hydrodynamic Flows in Imploding Fusion Plasmas on the National Ignition Facility

2025-04-07T08:33:18Z

Observation of Hydrodynamic Flows in Imploding Fusion Plasmas on the National Ignition Facility Schlossberg, D.J.; Grim, G.P.; Casey, D.T.; Moore, A.S.; Nora, R.; Bachmann, B.; Benedetti, L.R.; Bionta, R.M.; Eckart, M.J.; Field, J.E.; Fittinghoff, D.N.; Gatu Johnson, Maria; Geppert-Kleinrath, V.; Hartouni, E.P.; Hatarik, R.; Hsing, W.W.; Jarrott, L.C.; Khan, S.F.; Kilkenny, J.D.; Landen, O.L.; MacGowan, B.J.; Mackinnon, A.J.; Meaney, K.D.; Munro, D.H.; Nagel, S.R.; Pak, A.; Patel, P.K.; Spears, B.K.; Volegov, P.L.; Young, C.V. Inertial confinement fusion implosions designed to have minimal fluid motion at peak compression often show significant linear flows in the laboratory, attributable per simulations to percent-level imbalances in the laser drive illumination symmetry. We present experimental results which intentionally varied the Mode 1 drive imbalance by up to 4% to test hydrodynamic predictions of flows and the resultant imploded core asymmetries and performance, as measured by a combination of DT neutron spectroscopy and high-resolution x-ray core imaging. Neutron yields decrease by up to 50% and anisotropic neutron Doppler broadening increases by 20%, in agreement with simulations. Furthermore, a tracer jet from the capsule fill tube perturbation that is entrained by the hot spot flow confirms the average flow speeds deduced from neutron spectroscopy. Submitted for publication in Physical Review Letters

Screening-Current-Induced Strain Gradient on REBCO Conductor: An Experimental and Analytical Study With Small Coils Wound With Monofilament and Striated Multifilament REBCO Tapes

2025-04-07T09:11:22Z

Screening-Current-Induced Strain Gradient on REBCO Conductor: An Experimental and Analytical Study With Small Coils Wound With Monofilament and Striated Multifilament REBCO Tapes Li, Yi; Park, Dongkeun; Lee, Wooseung; Choi, Yoonhyuck; Tanaka, Hiromi; Bascuñán, Juan; Iwasa, Yukikazu Screening currents in REBCO conductors, induced by time-varying magnetic fields, not only affect the field quality of HTS coils but also cause strain gradients along REBCO tape width that may overstress REBCO conductors used in NMR and other high-field magnets. In this paper, we present results of an experimental and analytical study on screening-current-induced strain gradients, performed with small REBCO pancake coils. Because we believe that screening current effect is reduced in multifilament conductor, we have studied 2 test coils,φ150 mm, one wound with monofilament and the other with 3-striate/4-filament REBCO tapes. A 5-T/ 300-mm room-temperature bore magnet was used not only to excite a strong screening current but also apply the nonuniform Lorentz force to each coil at 4.2 K. Our experiment and analysis have quantitatively demonstrated that we can effectively suppress the screening-current effect on strain gradient, not surprisingly, by using striated multifilament REBCO conductor. Submitted for publication in IEEE Transactions on Applied Superconductivity

Quench Analysis of an LTS Quadrupole Triplet Magnet System for the IBS RAON In-Flight Fragment Separator

2025-04-07T08:58:01Z

Quench Analysis of an LTS Quadrupole Triplet Magnet System for the IBS RAON In-Flight Fragment Separator Lee, Wooseung; Park, Dongkeun; Iwasa, Yukukazu; Kim, Junseong; Lee, Jiho; Kim, Do Gyun In this paper we present quench analysis results of a Low-Temperature Superconducting (LTS) quadrupole triplet magnet system, a part of the In-flight Fragment (IF) separator of a heavy ion linear accelerator complex, named RAON, currently being constructed by the Institute of Basic Science (IBS). This magnet system is composed of three quadrupole magnets: a triplet, surrounded by iron yokes and embedding hexapole/octupole LTS coils for field correction. The magnet will be operated at 4.2 K in liquid helium. For reliable and safe operation of this complex superconducting system, quench and protection analysis with possible failure scenarios must be performed. In this paper, we first discuss probable quench scenarios and then present results of the quench propagation analysis on: 1) coil currents and voltages by multi-coil model circuit analysis; and 2) simulated temperature distribution inside each coil. Our quench analysis results show that the maximum voltage and temperature in each coil are below safety limits, 2000 V and 150 K, respectively, and confirm that this quadruple triplet magnet system is self-protecting. Submitted for publication in IEEE Transactions on Applied Superconductivity

Comparison of ablators for the polar direct drive exploding pusher platform

2025-04-08T04:12:41Z

Comparison of ablators for the polar direct drive exploding pusher platform Whitley, Heather D.; Kemp, G. Elijah; Yeamans, Charles B.; Walters, Zachary B.; Blue, Brent E.; Garbett, Warren J.; Schneider, Marilyn B.; Craxton, R. Stephen; Garcia, Emma M.; McKenty, Patrick W.; Gatu Johnson, Maria; Caspersen, Kyle; Castor, John I.; Däne, Markus; Ellison, C. Leland; Gaffney, Jim A.; Graziani, Frank R.; Klepeis, John E.; Kostinski, Natalie B.; Kritcher, Andrea L.; Lahmann, Brandon; Lazicki, Amy E.; Le, Hai P.; London, Richard A.; Maddox, Brian; Marshall, Michelle C.; Martin, Madison E.; Militzer, Burkhard; Nikroo, Abbas; Nilsen, Joseph; Ogitsu, Tadashi; Pask, John E.; Pino, Jesse E.; Rubery, Michael S.; Shepherd, Ronnie; Sterne, Philip A.; Swift, Damian C.; Yang, Lin; Zhang, Shuai We examine the performance of pure boron, boron carbide, high density carbon, and boron nitride ablators in the polar direct drive exploding pusher (PDXP) platform. The platform uses the polar direct drive con guration at the National Ignition Facility to drive high ion temperatures in a room temperature capsule and has potential applications for plasma physics studies and as a neutron source. The higher tensile strength of these materials compared to plastic enables a thinner ablator to support higher gas pressures, which could help optimize its performance for plasma physics experiments, while ablators containing boron enable the possiblity of collecting addtional data to constrain models of the platform. Applying recently developed and experimentally validated equation of state models for the boron materials, we examine the performance of these materials as ablators in 2D simulations, with particular focus on changes to the ablator and gas areal density, as well as the predicted symmetry of the inherently 2D implosion. Submitted for publication in High Energy Density Physics

The impact of disruptions on the economics of a tokamak power plant

2025-04-07T08:59:21Z

The impact of disruptions on the economics of a tokamak power plant Maris, Andrew D.; Wang, Allen; Rea, Cristina; Granetz, Robert; Marmar, Earl Tokamaks are often considered a leading candidate for near-term, cost-effective fusion energy, but are susceptible to sudden loss of confinement events called "disruptions.'' The threat of disruptions has garnered serious attention in research and development for the next generation of burning plasma experiments, such as ITER, but has received no thorough treatment in studies of magnetic fusion energy economics. In this paper, we provide a set of possible post-disruption recovery times based on technological and organization limitations, a list of various ways disruptions can add to the expense of a tokamak power plant (TPP), and a model for the cost of fusion electricity as a function of disruption-related parameters. We show how these tools can be used to more accurately compute the levelized cost of electricity (LCOE) of a TPP and quantify upper limits on disruption rate for TPPs such as DEMO-like and ARC-like concepts. We utilize these findings to highlight where future research can have a strong impact in neutralizing the ``showstopping'' potential of the disruption problem. Submitted for publication in Fusion Science and Technology

Multiphysics simulations of a steady-state lower hybrid current drive antenna for the FSNF

2025-04-07T08:55:46Z

Multiphysics simulations of a steady-state lower hybrid current drive antenna for the FSNF Wallace, Greg M.; Bohm, T.; Kessel, C.E. The Fusion Nuclear Science Facility (FNSF) is a proposed tokamak reactor with the mission to investigate operation of a fusion reactor in a nuclear environment. The high neutron fluence component of the FNSF mission requires steady-state operation for extremely long pulses (t_{pulse} ∼ months) at full power. Plasma sustainment and current drive will be critical components of a successful FNSF. COMSOL Multiphysics software is used for combined radiofrequency (RF) and thermal simulations of the lower hybrid current drive (LHCD) antenna system. These simu- lations consider the resistive RF losses in the antenna including realistic surface roughness and a range of potential materials. The thermal analysis adds volumetric nuclear heating, plasma heat flux on leading edges, and electromagnetic radiation from the plasma to the RF heating calculated by COMSOL. Additional neutronics calculations have been performed to determine the impact of these antenna designs on activated waste disposal for the materials considered. The simulations show that it is technically feasible to implement a fully-active multi-junction (FAM) rather than a passive-active multi-junction (PAM) style of antenna if the septum between adjacent waveguides is sufficiently wide and the thermal conductivity of the structural material is sufficiently high. The FAM has the benefit of higher achievable power density with respect to the PAM, which results in a more compact antenna with potentially lower impact on neutron shielding and tritium breeding. These considerations point to tungsten rather than steel as the preferred structural material in constructing the antenna. Submitted for publication in Fusion Science and Technology

Optimization of tritium breeding ratio in ARC reactor

2025-04-07T09:08:11Z

Optimization of tritium breeding ratio in ARC reactor Segantin, Stefano; Testoni, Raffaella; Hartwig, Zachary S.; Whyte, Dennis; Zucchetti, Massimo Affordable Robust Compact reactor is a conceptual design for a Tokamak conceived by Massachusetts Institute of Technology (MIT) researchers. The design of this tokamak is under development and update. One of the key parameters for fusion reactor power plants is the tritium breeding ratio (TBR), which has to guarantee the tritium self-sufficiency. The tritium inventory circulating in a fusion power plant must be minimized. In the meantime, to enhance plant’s economics, the amount of tritium generated and stored should be maximized, since it would be used to startup new reactors. Both of the aforementioned trends meet their best in a TBR as high as possible. In this work, ARC tritium breeding ratio is studied and optimized. Taking advantage of Monte Carlo neutron transport codes, several configurations of ARC’s blanket and vacuum vessel have been analyzed in order to find the most effective one for a high TBR. The study takes into account different materials for the structure, such as Inconel718, V-15Cr-5Ti and Eurofer97. Moreover, it scans different width of coolant’s channels and evaluates the effect of lithium-6 enrichment in the blanket looking for the best configuration in terms of TBR. Submitted for publication in Fusion Engineering and Design

Multi-species collisions for delta-f gyrokinetic simulations: Implementation and verification with GENE

2025-04-08T04:41:20Z

Multi-species collisions for delta-f gyrokinetic simulations: Implementation and verification with GENE Crandall, P.; Jarema, D.; Doerk, H.; Pan, Qingjiang; Merlo, G.; Görler, T.; Bañón Navarro, A.; Told, D.; Maurer, M., Jenko, F. A multi-species linearized collision operator based on the model developed by Sugama et al. has been implemented in the nonlinear gyrokinetic code, GENE. Such a model conserves particles, momentum, and energy to machine precision, and is shown to have negative definite free energy dissipation characteristics, satisfying Boltzmann’s H-theorem, including for realistic mass ratio. Finite Larmor Radius (FLR) effects have also been implemented into the local version of the code. For the global version of the code, the collision operator has been developed to allow for block-structured velocity space grids, allowing for computationally tractable collisional global simulations. The validity of the collision operator has been demonstrated by relaxation and conservation tests, as well as appropriate benchmarks. The newly implemented operator shall be used in future simulations to study magnetically confined fusion plasma turbulence and transport in more extreme regions with higher collisionality. Submitted for publication in Computer Physics Communications

On fault-mode phenomenon in no-insulation superconducting magnets: A preventive approach

2025-04-08T04:27:23Z

On fault-mode phenomenon in no-insulation superconducting magnets: A preventive approach Dong, Fangliang; Park, Dongkeun; Lee, Wooseung; Hao, Luning; Huang, Zhen; Bascuñán, Juan; Jin, Zhijian; Iwasa, Yukikazu Here, we present experimental and analytical results of a preventive approach applied to a fault-mode phenomenon caused by electrodes or power-source failure in a no-insulation (NI) high-temperature superconducting REBa2Cu3O7−x (REBCO, RE = rare earth) magnet. It is generally agreed that the NI magnets, at least those of laboratory scale, are self-protected from overheating and, therefore, from quenching, chiefly because of turn-to-turn current bypassing unique to NI. However, these NI magnets do experience unexpected quenches, e.g., when the current through the magnet suddenly drops due to the aforementioned fault-mode phenomenon. Here, we report this phenomenon of a sudden-discharging-triggered quench of an NI REBCO coil, conduction-cooled, and operated at 4.2 K. We also present our preventive approach for this phenomenon that relies on an appropriately designed resistor shunted across the coil terminals. With this shunt resistor, a quench was prevented by suppressing the quench initiating turn-to-turn heat and induced overcurrent within the NI winding, and the coil current decayed safely. Submitted for publication in Applied Physics Letters

Comment on 'Evolution Equationsof Nonlinearly Permissible, Coherent Hole Structures Propagating Persistently in Collisionless Plasmas'

2025-04-07T08:28:56Z

Comment on 'Evolution Equationsof Nonlinearly Permissible, Coherent Hole Structures Propagating Persistently in Collisionless Plasmas' Hutchinson, Ian H. Recent critical remarks, published in ``Annalen der Physik'', about the present author's analysis of electron and ion holes and their stability are addressed and shown to be misunderstandings and misrepresentations Submitted for publication in Annalen der Physik

Reflection and transmission of electromagnetic pulses at a planar dielectric interface -- theory and quantum lattice simulations

2025-04-07T08:43:52Z

Reflection and transmission of electromagnetic pulses at a planar dielectric interface -- theory and quantum lattice simulations Ram, Abhay K.; Vahala, George; Vahala, Linda; Soe, Min There is considerable interest in the application of quantum information science to advance computations in plasma physics. A particular point of curiosity is whether it is possible to take advantage of quantum computers to speed up numerical simulations relative to conventional computers. Many of the topics in fusion plasma physics are classical in nature. In order to implement them on quantum computers it will require couching a classical problem in the language of quantum mechanics. Electromagnetic waves are routinely used in fusion experiments to heat a plasma or to generate currents in the plasma. The propagation of electromagnetic waves is described by Maxwell equations with an appropriate description of the plasma as a dielectric medium. Before advancing to the tensor dielectric of a magnetized plasma, this paper considers electromagnetic wave propagation in a one-dimensional inhomogeneous scalar dielectric. The classic theory of scattering of plane electromagnetic waves at a planar interface, separating two different dielectric media, leads to Fresnel equations for reflection and transmission coefficients. In contrast to plane waves, this paper is on the reflection and transmission of a spatially confined electromagnetic pulse. Following an analytical formulation for the scattering of a Gaussian pulse, it is deduced that the maximum transmission coefficient for a pulse is $\sqrt{n_2/n_1}$ times that for a plane wave; the incident and transmitted pulses propagating in dielectric media with refractive indices $n_1$ and $n_2$, respectively. The analytical theory is complemented by numerical simulations using a quantum lattice algorithm for Maxwell equations. The algorithm, based on the Riemann-Silberstein-Weber representation of the electromagnetic fields and expressed in term of qubits, is an interleaved sequence of entangling operators at each lattice site and unitary streaming operators which transmit information from one site to an adjacent lattice site. Besides substantiating results from the theory for Gaussian pulses, numerical simulations show their validity for non-Gaussian pulses. Apart from their time-asymptotic forms, the simulations display an interplay between the incident, reflected, and transmitted pulses in the vicinity of the transition region between two dielectric media. Submitted for publication in AIP Advances

Intrinsic fluence non-uniformity in D3He backlit proton radiography

2025-04-07T08:38:40Z

Intrinsic fluence non-uniformity in D3He backlit proton radiography Johnson, Timothy M.; Shan, J.; Kishimori, R.; Cufari, M.J.; Adrian, Partick J.; Buschmann, B.; Chang, C.W.; Dannhoff, S.G.; DeVault, A.; Evans, Tucker E.; Foo, B.; Kunimune, Justin H.; Lawrence, Y.; Pearcy, Jacob A.; Reichelt, Benjamin L.; Russell, L.; Sutcliffe, G.D.; Vanderloo, N.L.; Vargas, J.; Wink, Christopher W.; Gatu Johnson, Maria; Séguin, Frederick H.; Petrasso, Richard D.; Frenje, Johan A.; Li, Chi-Kang Proton radiography is an essential diagnostic for studying magnetic fields in high energy density physics experiments. Protons are born in a fusion implosion, traverse the plasma, and are detected on CR-39 solid state nuclear track detectors. Here, it is shown that there is an intrinsic non-uniformity in ∼ 15 MeV D3He proton radiography data. The increasing angle between the proton trajectory and the center of the detector results in the proton traveling through more detector stack material. As the protons travel through more material and lose energy, the proton energy spectrum gets wider. Protons at the lower end of the spectrum can therefore be lost. The nominal filtering results in protons being ranged out at large angle, causing the intrinsic non-uniformity. This angular effect is confirmed with both OMEGA experiments and Geant4 simulations. It is found that reducing the filtering between the pieces of CR-39 in the detector stack mitigates this effect. Results from accelerator experiments show that this reduced filtering does not impact the detection efficiency of the CR-39. Accounting for this intrinsic fluence non-uniformity is essential for magnetic field reconstruction techniques using proton radiographs. Submitted for publication in Review of Scientific Instruments

Measurements of low-mode asymmetries in the areal density of laser-direct-drive deuterium–tritium cryogenic implosions on OMEGA using neutron spectroscopy

2025-04-07T09:00:17Z

Measurements of low-mode asymmetries in the areal density of laser-direct-drive deuterium–tritium cryogenic implosions on OMEGA using neutron spectroscopy Forrest, C.J.; Crilly, A.; Schwemmlein, A.; Appelbe, B.; Gatu Johnson, Maria; Betti, R.; Knauer, J.P.; Glebov, V. Yu.; Gopalaswamy, V.; Mannion, O.M.; Mohamed, Z.L.; Radha, P.B.; Regan, S.P.; Stoeckl, C.; Theobald, W. Areal density is one of the key parameters that determines the confinement time in inertial confinement fusion experiments, and low-mode asymmetries in the compressed fuel are detrimental to the implosion performance. The energy spectra from the scattering of the primary deuterium–tritium (DT) neutrons off the compressed cold fuel assembly are used to investigate low-mode nonuniformities in direct-drive cryogenic DT implosions at the Omega Laser Facility. For spherically symmetric implosions, the shape of the energy spectrum is primarily determined by the elastic and inelastic scattering cross sections for both neutron-deuterium and neutron-tritium kinematic interactions. Two highly collimated lines of sight, which are positioned at nearly orthogonal locations around the OMEGA target chamber, record the neutron time-of-flight signal in the current mode. An evolutionary algorithm is being used to extract a model-independent energy spectrum of the scattered neutrons from the experimental neutron time-of-flight data and is used to infer the modal spatial variations (l = 1) in the areal density. Experimental observations of the low-mode variations of the cold-fuel assembly (ρL0 + ρL1) show good agreement with a recently developed model, indicating a departure from the spherical symmetry of the compressed DT fuel assembly. Another key signature that has been observed in the presence of a low-mode variation is the broadening of the kinematic end-point due to the anisotropy of the dense fuel conditions. Submitted for publication in Review of Scientific Instruments

One and Two Dimensional Quantum Lattice Algorithms for Maxwell Equations in Inhomogeneous Scalar Dielectric Media I: Theory

2025-04-07T08:54:20Z

One and Two Dimensional Quantum Lattice Algorithms for Maxwell Equations in Inhomogeneous Scalar Dielectric Media I: Theory Vahala, George; Valhala, Linda; Soe, Min; Ram, Abhay K. A quantum lattice algorithm (QLA) is developed for Maxwell equations in scalar dielectric media using the Riemann-Silberstein representation on a Cartesian grid. For x-dependent and y-dependent dielectric inhomogeneities, the corresponding QLA requires a minimum of 8 qubits/spatial lattice site. This is because the corresponding Pauli spin matrices have off-diagonal components which permit the local collisional entanglement of these qubits. However, z-dependent inhomogeneities require a QLA with a minimum of 16 qubits/lattice site since the Pauli spin matrix σz is diagonal. For 2 dimensional inhomogeneities, one can readily couple the 8-8 qubit schemes for x-y variations. z-x and y-z variations can be treated by either a 16-8 qubit scheme or a 16-16 qubit representation. Submitted for publication in Radiation Effects and Defects in Solids

Experimental achievement and signatures of ignition at the National Ignition Facility

2025-04-08T04:30:48Z

Experimental achievement and signatures of ignition at the National Ignition Facility Zylstra, A.B.; Kritcher, A.L.; Hurricane, O.A.; Callahan, D.A.; Ralph, J.E.; Casey, D.T.; Pak, A.; Landen, O.L.; Bachmann, B.; Baker, K.L.; Berzak Hopkins, L.; Bhandarkar, S.D.; Biener, J.; Bionta, R.M.; Birge, N.W.; Braun, T.; Briggs, T.M.; Celliers, P.M.; Chen, H.; Choate, C.; Clark, D.S.; Divol, L.; Döppner, T.; Fittinghoff, D.; Edwards, M.J.; Gatu Johnson, Maria; Gharibyan, N.; Haan, S.; Hahn, K.D.; Hartouni, E.; Hinkel, D.E.; Ho, D.D.; Hohenberger, M.; Holder, J.P.; Huang, H.; Izumi, N.; Jeet, J.; Jones, O.; Kerr, S.M.; Khan, S.F.; Geppert Kleinrath, H.; Geppert Kleinrath, V.; Kong, C.; Lamb, K.M.; Le Pape, S.; Lemos, N.C.; Lindl, J.D.; MacGowan, B.J.; Mackinnon, A.J.; MacPhee, A.G.; Marley, E.V.; Meaney, K.; Millot, M.; Moore, A.S.; Newman, K.; Di Nicola, J.-M. G.; Nikroo, A.; Nora, R.; Patel, P.K.; Rice, N.G.; Rubery, M.S.; Sater, J.; Schlossberg, D.J.; Sepke, S.M.; Sequoia, K.; Shin, S.J.; Stadermann, M.; Stoupin, S.; Strozzi, D.J.; Thomas, C.A.; Tommasini, R.; Trosseille, C.; Tubman, E.R.; Volegov, P.L.; Weber, C.R.; Wild, C.; Woods, D.T.; Yang, S.T.; Young, C.V. An inertial fusion implosion on the National Ignition Facility, conducted on August 8, 2021 (N210808), recently produced more than a megajoule of fusion yield and passed Lawson’s criterion for ignition [Phys. Rev. Lett. 129, 075001 (2022)]. We describe the experimental improvements that enabled N210808 and present the first experimental measurements from an igniting plasma in the laboratory. Ignition metrics like the product of hot-spot energy and pressure squared, in the absence of self-heating, increased by ∼35%, leading to record values and an enhancement from previous experiments in the hot-spot energy (∼3×), pressure (∼2×), and mass (∼2×). These results are consistent with self-heating dominating other power balance terms. The burn rate increases by an order of magnitude after peak compression, and the hot-spot conditions show clear evidence for burn propagation into the dense fuel surrounding the hot spot. These novel dynamics and thermodynamic properties have never been observed on prior inertial fusion experiments. Submitted for publication in Physical Review E

Asymmetric one-dimensional slow electron holes

2025-04-08T04:47:41Z

Asymmetric one-dimensional slow electron holes Hutchinson, Ian H. Slow solitary positive-potential peaks sustained by trapped electron deficit in a plasma with asymmetric ion velocity distributions are in principle asymmetric, involving a potential change across the hole. It is shown theoretically how to construct such asymmetric electron holes, thus providing fully consistent solutions of the one-dimensional Vlasov-Poisson equation for a wide variety of prescribed background ion velocity distributions. Because of ion reflection forces experienced by the hole, there is generally only one discrete slow hole velocity that is in equilibrium. Moreover the equilibrium is unstable unless there is a local minimum in the ion velocity distribution, in which the hole velocity then resides. For stable equilibria with Maxwellian electrons, the potential drop across the hole is shown to be Delta\phi= 2/9 f''' (Te/e) (e\psi/m_i)^2 , where \psi is the hole peak potential, f''' is the third derivative of the background ion velocity distribution function at the hole velocity, and Te the electron temperature. Potential asymmetry is small for holes of the amplitudes usually observed, <~0.5Te/e. Submitted for publication in Physical Review E

How can slow plasma electron holes exist?

2025-04-08T04:30:19Z

How can slow plasma electron holes exist? Hutchinson, Ian H. One-dimensional analysis is presented of solitary positive potential plasma structures whose velocity lies within the range of ion distribution velocities that are strongly populated: "slow" electron holes. It is shown that to avoid the self-acceleration of the hole velocity away from ion velocities it must lie within a local minimum in the ion velocity distribution. Quantitative criteria for the existence of stable equilibria are obtained. The background ion distributions required are generally stable to ion-ion modes unless the electron temperature is much higher than the ion temperature. Since slow positive potential solitons are shown not to be possible without a significant contribution from trapped electrons, it seems highly likely that such observed slow potential structures are indeed electron holes. Submitted for publication in Physical Review E

Isotope effects on intrinsic rotation in hydrogen, deuterium and tritium plasmas

2025-04-07T08:37:38Z

Isotope effects on intrinsic rotation in hydrogen, deuterium and tritium plasmas Nave, M.F.F.; Delabie, E.; Ferreira, J.; Garcia, J.; King, D.; Lennholm, M.; Lomanowski, B.; Parra, F.; Rodriguez Fernandez, Pablo; Bernardo, J.; Baruzzo, M.; Barnes, M.; Casson, F.; Hillesheim, J.C.; Hubber, A.; Joffrin, E.; Kappatou, A.; Maggi, C.F.; Mauriya, A.; Meneses, L.; Romanelli, M.; Salzedas, F.; JET contributors The isotope effect on intrinsic rotation was studied at the JET tokamak. With the unique capability of JET to operate with Tritium, for the first time, experiments in Hydrogen, Deuterium and Tritium in ohmic plasmas were compared. Two rotation reversals per isotope type are observed in plasma density scans spanning the linear and the saturated Ohmic confinement regimes. A clear isotope mass dependence is observed at the higher densities. The magnitude of the core rotation was found to depend on isotope mass, with stronger co-current rotation observed in hydrogen. Change on intrinsic rotation characteristics coexist with a stronger thermal energy confinement in Tritium. Submitted for publication in Nuclear Fusion

Developing high performance RF heating scenarios on the WEST tokamak

2025-04-08T04:29:54Z

Developing high performance RF heating scenarios on the WEST tokamak Goniche, M.; Ostuni, V.; Bourdelle, C.; Maget, P.; Artaud, J.F.; Bernard, J.M.; Bobkov, V.; Bucalossi, J.; Clairet, F.; Colas, L.; Desgranges, C.; Delpech, L.; Devynck, P.; Dumont, R.; Ekedahl, A.; Fedorczak, N.; Garcia, J.; Gaspar, J.; Gil, C.; Guillemaut, C.; Gunn, J.; Hillairet, J.; Klepper, C.; Lau, C.; Lerche, E.; Lombard, G.; Manas, P.; Martin, E.H.; Mazon, D.; Meyer, O.; Morales, J.; Moreau, Ph.; Nardon, E.; Nouailletas, R.; Pegourié, B.; Peret, M.; Peysson, Y.; Regal-Mezin, X.; Sabot, R.; Shiraiwa, S.; Urbanzyck, G.; Vermare, L.; Vezinet, D.; Wallace, Greg M.; WEST Team High power experiments, up to 9.2 MW with LHCD and ICRH, have been carried out in the full tungsten tokamak WEST. Quasi non inductive discharges have been achieved allowing to extend the plasma duration to 53s with stationary conditions in particular with respect to tungsten contamination. Transitions in H mode are obtained lasting up to 4s with weak energy increment at the power crossing the separatrix is close to the threshold. Hot L mode plasmas (Te(0)>3keV) with a confinement time following the ITER L96 scaling are routinely obtained. The weak aspect ratio dependence of this scaling law is confirmed. Tungsten accumulation is generally not an operational issue on WEST. Difficulty of burning through tungsten can prevent from accessing to a hot core plasma in the ramp-up phase or can lead to rapid collapse of the central temperature when radiation is enhanced by a slight decrease of the temperature. Apart few pulses post-boronization, the plasma radiation is rather high (Prad/Ptot~50%) and is dominated by tungsten. This fraction does not vary as the RF power is ramped up and is quite similar in ICRH and/or LHCD heated plasmas. An estimate of the contribution of the RF antennas to the plasma contamination in tungsten is given. Submitted for publication in Nuclear Fusion

Suppression of first-wall interaction in negative triangularity plasmas on TCV

2025-04-07T09:20:20Z

Suppression of first-wall interaction in negative triangularity plasmas on TCV Han, Woonghee; Offeddu, N.; Golfinopoulos, T.; Theiler, C.; Tsui, C.K.; Boedo, J.A.; Marmar, E.S.; TCV Team Magnetically confined fusion plasmas with negative triangularity (d) exhibit greater L-mode confinement than with positive d. Recent experiments in the TCV and DIII-D tokamaks have correlated the confinement improvement to a reduction of fluctuations within the plasma core. We report on fluctuation measurements in the scrape-off layer (SOL) for −0.61 < d < +0.64 in limited and diverted ohmic L-mode plasmas; these reveal a strong reduction in SOL fluctuation amplitudes at d < −0.25, and, surprisingly, an almost full suppression of plasma interaction with the main-chamber first-wall, which could have important implications for the prospects of using negative d plasmas as a reactor solution. An exploration of several physical mechanisms suggests that a reduced connection length—intrinsic to negative d plasmas—plays a critical role in the origin of this phenomenon. Submitted for publication in Nuclear Fusion

A model investigation of the impact of lower hybrid wave scattering angle on current drive profile in EAST and Alcator C-Mod

2025-04-07T09:06:14Z

A model investigation of the impact of lower hybrid wave scattering angle on current drive profile in EAST and Alcator C-Mod Baek, Seung Gyou; Biswas, B.; Wallace, Greg M.; Bonoli, Paul T.; Ding, B.J.; Li, M.H.; Li, Y.C.; Wang, Y.F.; Wang, M.; Wu, C.B.; Yan, G.H.; Chen, J.; Zhai, X.; Garofalo, A.M.; Choi, W.; Poli, F.; Shiraiwa, S. Lower hybrid current drive (LHCD) is beneficial for developing a steady-state operation scenario in a tokamak. This paper conducts a modelling investigation to identify an optimum rotation angle of the initial lower hybrid perpendicular (to the background magnetic field) wavevector for best matching the experimental RF current profile. It is hypothesized that central RF power deposition widely observed in the present-day LHCD experiments arises from wave scattering by turbulence. In a standard model without considering such interactions, the predicted power deposition profile is generally broad with off-axis peaking, not in agreement with experimental observations. A heuristic approach is adopted by introducing a spectral broadening mechanism by modifying the initial orientation of the perpendicular wavevector. The ray-tracing/Fokker-Planck solver GENRAY/CQL3D is utilized within the python-based pi-scope framework. A focus is given to identify the perpendicular wavenumber orientation angle with respect to the magnetic surface normal vector at the initial ray location. Our modelling study shows that rotating the perpendicular wavevector in such a way as to increase the initial poloidal component is effective in reproducing the centrally peaked current profile observed in normal shear plasmas on both EAST and C-Mod. These waves can readily be absorbed to the central plasma, which reduces the sensitivity of the power deposition profile to a slight change of the plasma condition. The same approach is also found to help broaden the off-axis power deposition profile in a reverse-shear EAST plasma, leading to a better agreement with the experiment. The results presented here suggest that spectral modification arising from edge density fluctuations in a tokamak may need to be considered in understanding wave propagation and absorption. A further experimental and theoretical/modelling study is vital as a reverse approach is adopted in this study. Our work suggests that mitigation or control measures are critical for parasitic effects occurring on the first pass in a reactor regime. Submitted for publication in Nuclear Fusion

Observations of wall conditioning by means of boron powder injection in DIII-D H-mode plasmas

2025-04-07T08:51:53Z

Observations of wall conditioning by means of boron powder injection in DIII-D H-mode plasmas Bortolon, A.; Maingi, R.; Nagy, A.; Ren, J.; Duran, J.D.; Maan, A.; Donovan, D.C.; Boedo, J.A.; Rudakov, D.L.; Hyatt, A.W.; Wilks, Theresa M.; Shafer, M.W.; Samuell, C.M.; Fenstermacher, M.E.; Gilson, E.P.; Lunsford, R.; Mansfield, D.K.; Abrams, T.; Nazikian, R.; DIII-D team We report observations from the DIII-D tokamak indicating that boron (B) powder injection in tokamak plasmas improves wall conditions similarly to glow discharge boronization (GDB). Isotopically enriched B powder (B11 > 95%) was introduced gravitationally in a sequence of H-mode plasma discharges at rates up to ∼160 mg s−1 for durations up to 3 s. Boron injection to cumulative amounts ≤0.1 g appeared to improve wall conditions similarly to boronization, with indications of reduced wall fueling, reduced recycling at the outer strike point and reduced impurity content at breakdown. Post-mortem analysis of graphite samples exposed to far scrape-off layer plasma fluxes during boron injection confirm the formation of a B-C layer, with average surface composition B:C ∼ 1. The results suggest that injecting boron-rich powders in tokamak plasmas can effectively replenish boron films on carbon plasma facing components to improve wall conditions and extend the duration of the beneficial effects of GDB. Submitted for publication in Nuclear Fusion

Experimental studies of plasma-antenna coupling with the JET Alfven Eigenmode Active Diagnostic

2025-04-08T04:41:49Z

Experimental studies of plasma-antenna coupling with the JET Alfven Eigenmode Active Diagnostic Tinguely, R. Alex; Puglia, P.G.; Fil, N.; Dowson, S.; Porkolab, Miklos; Dvornova, A.; Fasoli, A.; Fitzgerlad, M.; Guillemot, V.; Huysmans, G.T.A.; Maslov, M.; Sharapov, S.; Testa, D.; JET contributors This paper presents a dedicated study of plasma-antenna (PA) coupling with the Alfven Eigenmode Active Diagnostic (AEAD) in JET. Stable AEs and their resonant frequencies f, damping rates gamma < 0, and toroidal mode numbers n are measured for various PA separations and limiter versus X-point magnetic configurations. Two stable AEs are observed to be resonantly excited at distinct low and high frequencies in limiter plasmas. The values of f and n do not vary with PA separation. However, |gamma| increases with PA separation for the low-f, but not high-f, mode, yet this may be due to slightly different edge conditions. The high-f AE is detected throughout the transition from limiter to X-point configuration, though its damping rate increases; the low-f mode, on the other hand, becomes unidentifiable. The linear resistive MHD code CASTOR is used to simulate the frequency scan of an AEAD-like external antenna. For the limiter pulses, the high-f mode is determined to be an n = 0 GAE, while the low-f mode is likely an n = 2 TAE. During the transition from limiter to X-point configuration, CASTOR indicates that n = 1 and 2 EAEs are excited in the edge gap. These results extend previous experimental studies in JET and Alcator C-Mod; validate the computational work performed by Dvornova et al 2020 Phys. Plasmas 27 012507; and provide guidance for the optimization of PA coupling in upcoming JET energetic particle experiments, for which the AEAD will aim to identify the contribution of alpha particles to AE drive during the DT campaign. Submitted for publication in Nuclear Fusion

Ion and electron acoustic bursts during anti-parallel magnetic reconnection driven by lasers

2025-04-07T09:24:36Z

Ion and electron acoustic bursts during anti-parallel magnetic reconnection driven by lasers Zhang, Shu; Chien, Abraham; Gao, Lan; Ji, Hantao; Blackman, Eric G.; Follett, Russ; Froula, Dustin H.; Katz, Joseph; Daughton, William; Li, Chi-Kang; Birkel, Andrew; Petrasso, Richard D.; Moody, John; Chen, Hui Magnetic reconnection converts magnetic energy into thermal and kinetic energy in plasma. Among the numerous candidate mechanisms, ion acoustic instabilities driven by the relative drift between ions and electrons (or equivalently, electric current) have been suggested to play a critical role in dissipating magnetic energy in collisionless plasmas. However, their existence and efectiveness during reconnection have not been well understood due to ion Landau damping and difculties in resolving the Debye length scale in the laboratory. Here we report a sudden onset of ion acoustic bursts measured by collective Thomson scattering in the exhaust of anti-parallel magnetically driven reconnection using high-power lasers. The ion acoustic bursts are followed by electron acoustic bursts with electron heating and bulk acceleration. We reproduce these observations with one- and two-dimensional particle-in-cell simulations in which an electron outfow jet drives ion acoustic instabilities, forming double layers. These layers induce electron two-stream instabilities that generate electron acoustic bursts and energize electrons. Our results demonstrate the importance of ion and electron acoustic dynamics during reconnection when ion Landau damping is inefective, a condition applicable to a range of astrophysical plasmas including near-Earth space, stellar fares and black hole accretion engines. Submitted for publication in Nature Physics

Yield degradation due to laser drive asymmetry in D3He backlit proton radiography experiments at OMEGA

2025-04-07T09:22:25Z

Yield degradation due to laser drive asymmetry in D3He backlit proton radiography experiments at OMEGA Johnson, Timothy M.; Birkel, Andrew; Ramirez, H.E.; Sutcliffe, G.D.; Adrian, Patrick J.; Glebov, V.Yu.; Sio, H.; Gatu Johnson, Maria; Frenje, Johan A.; Petrasso, Richard D.; Li, Chi-Kang Mono-energetic proton radiography is a vital diagnostic for numerous high-energy-density-physics, inertial-confinement-fusion, and laboratory-astrophysics experiments at OMEGA. With a large number of campaigns executing hundreds of shots, general trends in D3He backlighter performance are statistically observed. Each experimental configuration uses a different number of beams and drive symmetry, causing the backlighter to perform differently. Here, we analyze the impact of these variables on the overall performance of the D3He backlighter for proton-radiography studies. This study finds that increasing laser drive asymmetry can degrade the performance of the D3He backlighter. The results of this study can be used to help experimental designs that use proton radiography. Submitted for publication in Review of Scientific Instruments

A 1D Lyman-alpha Profile Camera for Plasma Edge Neutral Studies on the DIII-D Tokamak

2025-04-07T08:46:41Z

A 1D Lyman-alpha Profile Camera for Plasma Edge Neutral Studies on the DIII-D Tokamak Rosenthal, Aaron M.; Hughes, Jerry W.; Bortolon, A.; Laggner, F.M.; Wilks, Theresa M.; Vieira, R.; Leccacorvi, R.; Marmar, E.; Nagy, A.; Freeman, C.; Mauzey, D. A one dimensional, absolutely calibrated pinhole camera system was installed on the DIII-D tokamak to measure edge Lyman-alpha (Ly-a) emission from hydrogenic isotopes which can be used to infer neutral density and ionization rate pro les. The system is composed of two cameras, each providing a toroidal fan of twenty lines of sight, viewing the plasma edge on the inboard and outboard side of DIII-D. The cameras' views lie in a horizontal plane 77 cm below the midplane. At its tangency radius, each channel provides a radial resolution of approximately 2 cm full width at half maximum (FWHM) with a total coverage of 22 cm. Each camera consists of a rectangular pinhole, Ly-a reflective mirror, narrow-band Ly-a transmission fiter, and a 20 channel AXUV photodetector. The combined mirror and transmission fiter have a FWHM of 5 nm, centered near the Ly-a wavelength of 121.6 nm and is capable of rejecting signifi cant, parasitic carbon-III (C-III) emission from intrinsic plasma impurities. To provide a high spatial resolution measurement in a compact footprint, the camera utilizes advanced engineering and manufacturing techniques including 3D printing, high stability mirror mounts, and a novel alignment procedure. Absolutely calibrated, spatially resolved Ly-a brightness measurements utilize a bright, isolated line with low parasitic surface reflections and enable quantitative comparison to modeling to study divertor neutral leakage, main chamber fueling and radial particle transport. Submitted for publication in Review of Scientific Instruments

Deep modelling of plasma and neutral fluctuations from gas puff turbulence imaging

2025-04-07T08:45:49Z

Deep modelling of plasma and neutral fluctuations from gas puff turbulence imaging Mathews, Abhilash; Terry, James L.; Baek, Seung Gyou; Hughes, Jerry W.; Kuang, Adam Q.; LaBombard, Brian; Miller, M.A.; Zweben, S.J.; Stotler, D.; Reiter, D.; Zholobenko, W.; Goto, M. The role of turbulence in setting boundary plasma conditions is presently a key uncertainty in projecting to fusion energy reactors. To robustly diagnose edge turbulence, we develop and demonstrate a technique to translate brightness measurements of HeI line radiation into local plasma fluctuations via a novel integrated deep learning framework that combines neutral transport physics and collisional radiative theory for the $3^3 D - 2^3 P$ transition in atomic helium. The tenets for experimental validity are reviewed, illustrating that this turbulence analysis for ionized gases is transferable to both magnetized and unmagnetized environments with arbitrary geometries. Based upon fast camera data on the Alcator C-Mod tokamak, we present the first 2-dimensional time-dependent experimental measurements of the turbulent electron density, electron temperature, and neutral density revealing shadowing effects in a fusion plasma using a single spectral line. Submitted for publication in Review of Scientific Instruments

Some comments on unitary qubit lattice algorithms for classical problems

2025-04-08T04:12:37Z

Some comments on unitary qubit lattice algorithms for classical problems Anderson, Paul; Finegold-Sachs, Lillian; Vahala, George; Vahala, Linda; Ram, Abhay K.; Soe, Min; Koukoutsis, Efstratios; Hizandis, Kyriakos A qubit lattice algorithm (QLA), which consists of a set of interleaved unitary collision-streaming operators, is developed for electromagnetic wave propagation in tensor dielectric media. External potential operators are required to handle gradients in the refractive indices, and these operators are typically non-unitary but sparse. A similar problem arises in the QLA for the Korteweg-de Vries equation, as the potential operator that models the KdV nonlinear term is also non-unitary. Several QLAs are presented here that avoid the need of this non-unitary potential operator by perturbing the collision operator. These QLAs are fully unitary. Submitted for publication in Radiation Effects and Defects in Solids

One and Two Dimensional Quantum Lattice Algorithms for Maxwell Equations in Inhomogeneous Scalar Dielectric Media. II: Simulations

2025-04-07T09:01:36Z

One and Two Dimensional Quantum Lattice Algorithms for Maxwell Equations in Inhomogeneous Scalar Dielectric Media. II: Simulations Vahala, George; Soe, Min; Vahala, Linda; Ram, Abhay K. Long time quantum lattice algorithm (QLA) simulations are performed for the mul- tiple reflection-transmission of an initial electromagnetic pulse propagating normally to a boundary layer region joining two media of different refractive index. For these one dimensional (1D) sim- ulations, there is excellent agreement between x-, y- and z- representations, as well as very good agreement with nearly all the standard plane wave boundary condition results for reflection and transmission off a dielectric discontinuity. In the QLA simulation, no boundary conditions are im- posed at the continuous, but sharply increasing, dielectic boundary layers. Two dimensional (2D) QLA scattering simulations in the x-z plane are performed for an electromagnetic pulse interacting with a conical dielectric obstacle for the 8-16 qubit model. Submitted for publication in Radiation Effects and Defects in Solids

Scattering of Radio Frequency Waves by Density Filaments

2025-04-07T09:01:12Z

Scattering of Radio Frequency Waves by Density Filaments Ram, Abhay K.; Hizanidis, K.; Bairaktaris, F.; Papadopoulos, A.; Valvis, S.-I. The edge region and the scrape-off layer of magnetically confined fusion devices, like tokamaks and stellarators, are replete with turbulent plasma that is a mixture of coherent, blob or filament like, structures [1] and incoherent fluctuations [2]. The variation in the density due to turbulence can be comparable to or greater than the ambient density [2]. As part of an overall effort to optimize the efficiency of operation, radio frequency (RF) waves are commonly used for heating fusion plasmas and, in tokamaks, for generating plasma current needed for confinement and controlling instabilities. The RF waves are excited by antenna structures that are placed near the wall of a fusion device. In order to deliver energy and momentum to charged particles in the core of fusion plasmas, RF waves have to propagate through the turbulent plasma. In present fusion devices, the scrap-off layer and the edge plasma region is of the order of a few centimeters. In reactor type devices, like ITER, this region is expected to be of the order of tens of centimeters. Since the efficiency of operation of a fusion reactor is of prime importance, it is imperative that we understand the effect of turbulence on RF waves. The fluctuations in density lead to changes in the plasma permittivity. As in conventional electrodynamics, the propagation of RF waves through different dielectric media is subject to reflection, refraction, and diffraction. In this paper, we summarize our theoretical and computational studies on the propagation of RF waves through filamentary structures present in the scrape-off layer. Submitted for publication in Radiation Effects and Defects in Solids

Time-resolved turbulent dynamo in a laser plasma

2025-04-08T04:07:38Z

Time-resolved turbulent dynamo in a laser plasma Bott, Archie F.A.; Tzeferacos, Petros; Chen, Laura; Palmer, Charlotte A.J.; Rigby, Alexandra; Bell, Anthony R.; Bingham, Robert; Birkel, Andrew; Graziani, Carlo; Froula, Dustin H.; Katz, Joseph; Koenig, Michel; Kunz, Matthew W.; Li, Chi-Kang; Meinecke, Jena; Miniati, Francesco; Petrasso, Richard D.; Park, Hye-Sook; Remington, Bruce A.; Reville, Brian; Ross, J. Steven; Ryu, Dongsu; Ryutov, Dmitri; Séguin, Fredrick H.; White, Thomas G.; Schekochihin, Alexander A.; Lamb, Donald Q.; Gregori, Gianluca Understanding magnetic-field generation and amplification in turbulent plasma is essential to account for observations of magnetic fields in the universe. A theoretical framework attributing the origin and sustainment of these fields to the so-called fluctuation dynamo was recently validated by experiments on laser facilities in low-magnetic-Prandtl-number plasmas (Pm<1). However, the same framework proposes that the fluctuation dynamo should operate differently when Pm≳1, the regime relevant to many astrophysical environments such as the intracluster medium of galaxy clusters. This paper reports an experiment that creates a laboratory Pm≳1 plasma dynamo. We provide a time-resolved characterization of the plasma’s evolution, measuring temperatures, densities, flow velocities, and magnetic fields, which allows us to explore various stages of the fluctuation dynamo’s operation on seed magnetic fields generated by the action of the Biermann-battery mechanism during the initial drive-laser target interaction. The magnetic energy in structures with characteristic scales close to the driving scale of the stochastic motions is found to increase by almost three orders of magnitude and saturate dynamically. It is shown that the initial growth of these fields occurs at a much greater rate than the turnover rate of the driving-scale stochastic motions. Our results point to the possibility that plasma turbulence produced by strong shear can generate fields more efficiently at the driving scale than anticipated by idealized magnetohydrodynamics (MHD) simulations of the nonhelical fluctuation dynamo; this finding could help explain the large-scale fields inferred from observations of astrophysical systems. Submitted for publication in Proceedings of the National Academy of Science

Physics of runaway electrons with Shattered Pellet Injection at JET

2025-04-07T08:30:31Z

Physics of runaway electrons with Shattered Pellet Injection at JET Reux, C.; Paz-Soldan, C.; Eidietis, N.; Lehnen, M.; Aleynikov, P.; Silburn, S.; Bandaru, V.; Ficker, O.; Hoelzl, M.; Hollmann, E.M.; Jachmich, S.; Joffrin, E.; Lomas, P.J.; Rimini, F.; Baylor, L.; Bleasdale, A.; Calacci, L.; Causa, F.; Carnevale, D.; Coffey, I.; Craven, D.; Dal Molin, A.; de la Luna, E.; De Tommasi, G.; Garcia, J.; Gebhart, T.; Giacomelli, L.; Huber, A.; Khilkevich, E.; Lowry, C.; Macusova, E.; Manzanares, A.; Nocente, M.; Panontin, E.; Papp, G.; Pautasso, G.; Peacock, A.; Plyusnin, V.; Shevelev, A.; Shiraki, D.; Commariva, C.; Sozzi, C.; Sridhar, S.; Sweeney, Ryan; Szepesi, G.; Tinguely, R. Alex; Wilson, J.; JET contributors Runaway electrons created during tokamak disruptions pose a threat to a reliable operation of future larger machines. Experiments using Shattered Pellet Injection (SPI) have been carried out at the JET tokamak to investigate ways to prevent their generation or suppress them if avoidance is not sufficient. Avoidance is possible if the SPI contains a sufficiently low fraction of high-Z material, or if it is red early in advance of a disruption prone to runaway generation. These results are consistent with previous similar fi ndings obtained with Massive Gas Injection. Suppression of an already accelerated beam is not efficient using High-Z material, but deuterium leads to harmless terminations without heat loads. This effect is the combination of a large MHD instability scattering runaway electrons on a large area and the absence of runaway regeneration during the subsequent current collapse thanks to the flushing of high-Z impurities from the runaway companion plasma. This effect also works in situations where the runaway beam moves upwards and undergoes scraping-off on the wall. Submitted for publication in Plasma Physics and Controlled Fusion

Effects of Neoclassical Tearing Modes and Toroidal Field Ripple on Lost Alpha Power in the SPARC Tokamak

2025-04-07T08:38:12Z

Effects of Neoclassical Tearing Modes and Toroidal Field Ripple on Lost Alpha Power in the SPARC Tokamak Braun, A.E.; Kramer, G.J.; Tinguely, R. Alex; Scott, S.D.; Sweeney, Ryan Using the SPIRAL Monte Carlo, full particle-orbit simulation code [Kramer PPCF 2013], we investigate the effects of neoclassical tearing modes (NTMs) and toroidal field (TF) ripple on alpha power losses during steady-state operation of the SPARC primary reference discharge [Creely JPP 2020, Rodriguez-Fernandez JPP 2020]. Model perturbations for TF ripple and the m/n = 2/1 and 3/2 NTMs with exaggerated widths selected based on an H-mode plasma approaching thermal quench are added to a simulated SPARC magnetic equilibrium through which marker particles are tracked. The 3/2 and 2/1 NTMs are located at ρpol ∼ 0.76 and ρpol ∼ 0.86 respectively, well positioned to increase alpha particle transport into and within an outer lossy region of the plasma beyond ρpol ∼ 0.8 where over 95% of lost alpha particles are born [Scott JPP 2020]. Total alpha power losses are shown to increase modestly from 1.73% lost at a minimum to 2.34% lost at a maximum, and alpha particle surface power densities form localized hotspots on the first-wall near the lowfield side midplane due to NTMs and TF ripple. We establish a conservative upper limit for first-wall alpha surface power densities on a toroidally symmetric wall for typical, flattop operation and motivate the consideration of NTMs in the design of three dimensional limiter surfaces for SPARC. Submitted for publication in Plasma Physics and Controlled Fusion

Quantum Computing Perspective for Electromagnetic Wave Propagation in Cold Magnetized Plasma

2025-04-07T08:39:37Z

Quantum Computing Perspective for Electromagnetic Wave Propagation in Cold Magnetized Plasma Koukoutsis, Efstratios; Hizanidis, Kyriakos; Vahala, George; Soe, Min; Vahala, Linda; Ram, Abhay K. Electromagnetic waves are an inherent part of all plasmas - laboratory fusion plasmas or astrophysical plasmas. The conventional methods for studying properties of electromagnetic waves rely on discretization of Maxwell equations suitable for implementing on classical, present day, computers. The traditional methodology is not efficient for quantum computing implementation - a future computational source offering a tantalizing possibility of enormous speed up and a significant reduction in computational cost. This paper addresses two topics relevant to implementing Maxwell equations on a quantum computer. The first is on formulating a quantum Schrödinger representation of Maxwell equations for wave propagation in a cold, inhomogeneous, and magnetized plasma. This representation admits unitary, energy preserving, evolution and conveniently lends itself to appropriate discretization for a quantum computer. Riding on the coattails of these results, the second topic is on developing a sequence of unitary operators which form the basis for a qubit lattice algorithm (QLA). The QLA, suitable for quantum computers, can be implemented and tested on existing classical computers for accuracy as well as scaling of computational time with the number of available processors. In order to illustrate the QLA for Maxwell equations, results are presented from a time evolving, full wave simulation of propagation and scattering of an electromagnetic wave packet by non-dispersive dielectric medium localized in space. Submitted for publication in Physics of Plasmas

Stability and Transport of Gyrokinetic Critical Pedestals

2025-04-08T04:32:37Z

Stability and Transport of Gyrokinetic Critical Pedestals Parisi, Jason; Oakleigh Nelson, Andrew; Guttenfelder, Walter; Gaur, Rahul; Berkery, John W.; Kaye, Stanley M.; Barada, Kshitish Kumar; Clauser, Cesar F.; Diallo, Ahmed; Hatch, David R.; Kleiner, Andreas; Lampert, Mate; Macwan, Tanmay; Mendard, Jonathan E. A gyrokinetic threshold model for pedestal width-height scaling prediction is applied to multiple devices. A shaping and aspect-ratio scan is performed on NSTX equilibria, finding $\Delta_{\mathrm{ped}} = 0.92 A^{1.04} \kappa^{-1.24} 0.38^{\delta} \beta_{\theta,\mathrm{ped}}^{1.05}$ for the wide-pedestal branch with pedestal width $\Delta_{\mathrm{ped}}$, aspect-ratio $A$, elongation $\kappa$, triangularity $\delta$, and normalized pedestal height $\beta_{\theta,\mathrm{ped}}$. A width-transport scaling is found to vary significantly if pedestal height is varied either with fixed density or fixed temperature, showing how fueling and heating sources affect the pedestal density and temperature profiles for the kinetic-ballooning-mode (KBM) limited profiles. For an NSTX equilibrium, at fixed density, the wide-branch is $\Delta_{\mathrm{ped} } = 0.028 \left(q_e/\Gamma_e - 1.7 \right)^{1.5} \sim \eta_e ^{1.5}$ and at fixed temperature $\Delta_{\mathrm{ped} } = 0.31 \left(q_e/\Gamma_e - 4.7 \right)^{0.85} \sim \eta_e ^{0.85}$ where $q_e$ and $\Gamma_e$ are turbulent electron heat and particle fluxes and $\eta_e = \nabla \ln T_e / \nabla \ln n_e$ for electron temperature $T_e$ and density $n_e$. Pedestals close to the KBM limit are shown to have modified turbulent transport coefficients compared to strongly driven KBMs. The role of flow-shear is studied as a width-height scaling constraint and pedestal saturation mechanism for a standard and lithiated wide pedestal discharge. Finally, the stability, transport, and flow-shear constraints are combined and examined for a NSTX experiment. Submitted for publication in Nuclear Fusion

Summary report of the 4th IAEA Technical Meeting on Fusion Data Processing, Validation and Analysis (FDPVA)

2025-04-08T04:21:56Z

Summary report of the 4th IAEA Technical Meeting on Fusion Data Processing, Validation and Analysis (FDPVA) Gonzalez de Vincente, S.M.; Mazon, D.; Xu, M.; Pinches, S.; Churchill, M.; Dinklage, A.; Fischer, R.; Murari, A.; Rodriguez Fernandez, Pablo; Stillerman, J.; Vega, J.; Verdoolaege, G. The objective of the fourth Technical Meeting on Fusion Data Processing, Validation and Analysis was to provide a platform during which a set of topics relevant to fusion data processing, validation and analysis are discussed with the view of extrapolating needs to next step fusion devices such as ITER. The validation and analysis of experimental data obtained from diagnostics used to characterize fusion plasmas are crucial for a knowledge-based understanding of the physical processes governing the dynamics of these plasmas. This paper presents the recent progress and achievements in the domain of plasma diagnostics and synthetic diagnostics data analysis (including image processing, regression analysis, inverse problems, deep learning, machine learning, big data and physics-based models for control) reported at the meeting. The progress in these areas highlight trends observed in current major fusion confinement devices. A special focus is dedicated on data analysis requirements for ITER and DEMO with a particular attention paid to Artificial Intelligence for automatization and improving reliability of control processes. Submitted for publication in Nuclear Fusion

Stability analysis of alpha driven toroidal Alfvén eigenmodes observed in JET deuterium-tritium internal transport barrier plasmas

2025-04-07T09:06:49Z

Stability analysis of alpha driven toroidal Alfvén eigenmodes observed in JET deuterium-tritium internal transport barrier plasmas Fitzgerald, M.; Dumont, R.; Keeling, D.; Mailloux, J.; Sharapov, S.; Dreval, M.; Figueiredo, A.; Coelho, R.; Ferreira, J.; Rodrigues, P.; Nabais, F.; Borba, D.; Stancar, Z.; Szepesi, G.; Tinguely, R. Alex; Puglia, P.G.; Oliver, H.J.C.; Kiptily, V.; Baruzzo, M.; Lennholm, M.; Siren, P.; Garcia, J.; Maggi, C.F.; JET contributors A Toroidal Alfvén eigenmode (TAE) has been observed to be driven by alpha particles in a JET deuterium-tritium internal transport barrier plasma. The observation occurred 50ms after the removal of neutral beam heating (NBI). The mode is observed on magnetics, soft-xray, interferometry and reflectometry measurements. We present detailed stability calculations using a similar tool set validated during deuterium only discharges. These calculations strongly support the conclusion that the observed mode is a TAE, and that this mode was destabilized by alpha particles. Non-ideal effects from the bulk plasma are interpreted as responsible for suppressing the majority of TAEs which were also driven by alpha particles, but the mode that matches the observations is predicted to be exceptional in the weakness of these non-ideal effects. This mode located far from the core on the outboard midplane is found to be driven by both trapped and passing particles despite alpha particles originating in the core. Submitted for publication in Nuclear Fusion

Toroidal Alfven eigenmodes observed in low power JET deuterium-tritium plasmas

2025-04-08T04:09:59Z

Toroidal Alfven eigenmodes observed in low power JET deuterium-tritium plasmas Oliver, H.J.C.; Sharapov, S.E.; Stancar, Z.; Fitzgerald, M.; Tholerus, E.; Breizman, B.; Dreval, M.; Ferreira, J.; Figueiredo, A.; Garcia, J.; Hawkes, N.; Keeling, D.L.; Puglia, P.G.; Rodrigues, P.; Tinguely, R. Alex; JET contributors The Joint European Torus (JET) recently carried out an experimental campaign using a plasma consisting of both deuterium (D) and tritium (T). We observed a high-frequency mode using a reflectometer and an interferometer in a D-T plasma heated with low power neutral beam injection, PNBI = 11.6 MW. This mode was observed at a frequency f = 156 kHz and was located deep in the plasma. The observed mode was identified as a toroidal Alfven eigenmode (TAE) using the linear MHD code, MISHKA. The stability of 21 modes that match experimental measurements was investigated. Beam ions and fusion-born alpha particles were modelled using the full orbit particle tracking code LOCUST, which produces smooth distribution functions suitable for stability calculations without analytical fits or the use of moments. We calculated the stability of the 21 candidate modes using the HALO code, which models the wave-particle interaction. These calculations revealed that beam ions can drive TAEs with toroidal mode numbers n ≥ 8 with linear growth rates γd/ω ∼ 1%, while TAEs with n < 8 are damped by the beam ion population. This finding was supported by a simple analytical model. Alpha particles drive modes with significantly smaller linear growth rates, γα/ω ≲ 0.1% due to the low alpha power generated almost exclusively by beam-thermal fusion reactions. Non-ideal effects were calculated using complex resistivity in the CASTOR code, leading to an assessment of radiative, collisional, and continuum damping for all 21 candidate modes. Ion Landau damping was modelled using Maxwellian distribution functions for bulk D and T ions in HALO. Radiative damping, the dominant damping mechanism, suppresses modes with high toroidal mode numbers. Comparing the drive from energetic particles with damping from thermal particles, we find all but one of the candidate modes are damped. The single net-driven n = 9 TAE with a net growth rate γ/ω = 0.02% matches experimental observations with a lab frequency f = 163kHz and location R = 3.31m. The TAE was driven by co-passing particles through the v∥ = vA/5 resonance, with additional sideband resonances contributing significant drive. Submitted for publication in Nuclear Fusion

Comparison of Core Ar^17+ and Mo^32+ Toroidal Rotation in C-Mod Plasmas

2025-04-08T04:15:44Z

Comparison of Core Ar^17+ and Mo^32+ Toroidal Rotation in C-Mod Plasmas Rice, John E.; Angioni, C.; Cao, N.M.; Reinke, M.L. Core (r/a < 0.5) toroidal rotation from argon (Ar^17+, 40 AMU) and molybdenum (Mo^32+, 96 AMU) ions has been compared in C-Mod tokamak plasmas over a wide range of operating conditions and confinement schemes, including Ohmic L-mode in the linear and saturated regimes, ICRF heated I-mode and H-mode, as well as in discharges with induced locked modes and with external current and rotation drive. In all cases the velocities of the two impurities are identical within about 5%, for a range between -60 and +80 km/s. This is in general agreement with the predictions of neo-classical theory. Submitted for publication in Nuclear Fusion

Runaway electron deconfinement in SPARC and DIII-D by a passive 3D coil

2025-04-07T08:59:43Z

Runaway electron deconfinement in SPARC and DIII-D by a passive 3D coil Izzo, V.A.; Pusztai, I.; Särkimäki, K.; Sundström, A.; Garnier, D.; Weisberg, D.; Tinguely, R. Alex; Paz-Soldan, C.; Granetz, R.S.; Sweeney, Ryan The operation of a 3D coil (passively driven by the current quench loop voltage) for the deconfinement of runaway electrons is modeled for disruption scenarios in the SPARC and DIII-D tokamaks. Nonlinear MHD modeling is carried out with the NIMROD code including time-dependent magnetic field boundary conditions to simulate the effect of the coil. Further modeling in some cases uses the ASCOT5 code to calculate advection and diffusion coefficients for runaway electrons based on the NIMROD-calculated fields, and the DREAM code to compute the runaway evolution in the presence of these transport coefficients. Compared with similar modeling in Tinguely, et al [2021 Nucl. Fusion 61 124003], considerably more conservative assumptions are made with the ASCOT5 results, zeroing low levels of transport, particularly in regions in which closed flux surfaces have reformed. Of three coil geometries considered in SPARC, only the n = 1 coil is found to have sufficient resonant components to suppress the runaway current growth. Without the new conservative transport assumptions, full suppression of the RE current is maintained when the TQ MHD is included in the simulation or when the RE current is limited to 250kA, but when transport in closed ux regions is fully suppressed, these scenarios allow RE beams on the order of 1-2MA to appear. Additional modeling is performed to consider the effects of the close ideal wall. In DIII-D, the current quench is modeled for both limited and diverted equilibrium shapes. In the limited shape, the onset of stochasticity is found to be insensitive to the coil current amplitude and governed largely by the evolution of the safety-factor pro le. In both devices, prediction of the q-pro le evolution is seen to be critical to predicting the later time effects of the coil. Submitted for publication in Nuclear Fusion

Simultaneous measurements of unstable and stable Alfven Eigenmodes in JET

2025-04-07T08:49:25Z

Simultaneous measurements of unstable and stable Alfven Eigenmodes in JET Tinguely, R. Alex; Gonzalez-Martin, J.; Puglia, P.G.; Fil, N.; Dowson, S.; Porkolab, Miklos; Kumar, I.; Podestà, M.; Baruzzo, M.; Fasoli, A.; Kazakov, Ye.O.; Nave, M.F.F.; Nocente, M.; Ongena, J.; Stancar, Z.; JET Contributors In this paper, we report the novel experimental observation of both unstable and stable Toroidicity-induced Alfven Eigenmodes (TAEs) measured simultaneously in a JET tokamak plasma. The three-ion-heating scheme (D-DNBI-3He) is employed to accelerate deuterons to MeV energies, thereby destabilizing TAEs with toroidal mode numbers n = 3-5, each decreasing in mode amplitude. At the same time, the Alfven Eigenmode Active Diagnostic resonantly excites a stable n = 6 TAE with total normalized damping rate ~1-4%. Hybrid kinetic-MHD modeling with codes NOVA-K and MEGA both find eigenmodes with similar frequencies, mode structures, and radial locations as in experiment. NOVA-K demonstrates good agreement with the n = 3, 4, and 6 TAEs, matching the damping rate of the n = 6 mode within uncertainties and identifying radiative damping as the dominant contribution. Improved agreement is found with MEGA for all modes: the unstable n = 3-5 and stable n = 2, 6 modes, with the latter two stabilized by higher intrinsic damping and lower fast ion drive, respectively. While some discrepancies remain to be resolved, this unique validation effort gives us confidence in TAE stability predictions for future fusion devices. Submitted for publication in Nuclear Fusion

Diverted negative triangularity plasmas on DIII-D: The benefit of high confinement without the liability of an edge pedestal

2025-04-07T09:23:38Z

Diverted negative triangularity plasmas on DIII-D: The benefit of high confinement without the liability of an edge pedestal Marinoni, Alessandro; Austin, M.E.; Hyatt, A.W.; Saarelma, S.; Scotti, F.; Yan, Z.; Chrystal, C.; Coda, S.; Glass, F.; Hanson, J.M.; McLean, A.G.; Pace, D.C.; Paz-Soldan, C.; Petty, C.C.; Porkolab, Miklos; Schmitz, L.; Sciortino, Francesco; Smith, S.P.; Thome, K.E.; Turco, F.; DIII-D Team Diverted discharges at negative triangularity on the DIII-D tokamak sustain normalized confinement and pressure levels typical of standard H-mode scenarios (H98y2~1, βN~3) without developing an edge pressure pedestal, despite the auxiliary power far exceeding the L → H power threshold expected from conventional scaling laws. The power degradation of confinement is substantially weaker than the ITER-89P scaling, resulting in a confinement factor that improves with increasing auxiliary power. The absence of the edge pedestal is beneficial in several aspects, such as eliminating the need for active mitigation or suppression of edge localized modes, low impurity retention and a reconstructed scrape-off layer heat flux width at the mid-plane that exceeds the ITPA multi-machine scaling law by up to 50%. Together with technological advantages granted by placing the divertor at larger radii, plasmas at Negative Triangularity without an edge pedestal feature both core confinement and power handling characteristics that are potentially suitable for operation in future fusion reactors. Submitted for publication in Nuclear Fusion

WEST actively cooled load resilient ion cyclotron resonance heating system results

2025-04-07T08:42:49Z

WEST actively cooled load resilient ion cyclotron resonance heating system results Hillairet, J.; Mollard, P.; Colas, L.; Helou, W.; Urbanczyk, G.; Bernard, J.-M.; Delaplanche, J.-M.; Durand, F.; Faure, N.; Garibaldi, P.; Lombard, G.; Bourdelle, C.; Desgranges, C.; Delmas, E.; Dumont, R.; Ekedahl, A.; Ferlay, F.; Goniche, M.; Guillemaut, C.; Hoang, G.T.; Maget, P.; Volpe, R.; Song, Y.; Yang, Q.; Chen, Z.; Wang, Y.; Xu, H.; Yuan, S.; Zhao, Y.; Durodie, F.; Lerche, E.; Ragona, R.; Bertelli, N.; Ono, M.; Shiraiwa, S.; Bobkov, V.; Klepper, C.; Lau, C.; Martin, E.; Lu, B.; Maggiora, R.; Milanesio, D.; Vulliez, K.; Wallace, Greg W.; WEST Team Three identical new WEST ion cyclotron resonance heating (ICRH) antennas have been designed, assembled then commissioned on plasma from 2013 to 2019. The WEST ICRH system is both load-resilient and compatible with long-pulse operations. The three antennas have been successfully operated together on plasma in 2019 and 2020, with up to 5.8 MW of coupled power. The load resilience capability has been demonstrated and the antenna feedback controls for phase and matching have been developed. The breakdown detection systems have been validated and successfully protected the antennas. The use of ICRH in combination with lower hybrid has triggered the first high confinement mode transitions identified on WEST. Submitted for publication in Nuclear Fusion

A novel measurement of marginal Alfven Eigenmode stability during high power auxiliary heating in JET

2025-04-08T04:24:16Z

A novel measurement of marginal Alfven Eigenmode stability during high power auxiliary heating in JET Tinguely, R. Alex; Fil, N.; Puglia, P.G.; Dowson, S.; Porkolab, Miklos; Guillemot, V.; Podestà, M.; Baruzzo, M.; Dumont, R.; Fasoli, A.; Fitgerald, M.; Kazakov, Ye.O.; Nave, M.F.F.; Nocente, M.; Ongena, J.; Sharapov, S.E.; Stancar, Z.; JET Contributors The interaction of Alfven Eigenmodes (AEs) and energetic particles is one of many important factors determining the success of future tokamaks. In JET, eight in-vessel antennas were installed to actively probe stable AEs with frequencies ranging 25-250 kHz and toroidal mode numbers |n| < 20. During the 2019-2020 deuterium campaign, almost 7500 resonances and their frequencies f0, net damping rates \gamma < 0, and toroidal mode numbers were measured in almost 800 plasma discharges. From a statistical analysis of this database, continuum and radiative damping are inferred to increase with edge safety factor, edge magnetic shear, and when including non-ideal effects. Both stable AE observations and their associated damping rates are found to decrease with |n|. Active antenna excitation is also found to be ineffective in H-mode as opposed to L-mode; this is likely due to the increased edge density gradient's effect on accessibility and ELM-related noise's impact on mode identification. A novel measurement is reported of a marginally stable, edge-localized Ellipticity-induced AE probed by the antennas during high-power auxiliary heating (ICRH and NBI) up to 25 MW. NOVA-K kinetic-MHD simulations show good agreement with experimental measurements of f0, \gamma, and n, indicating the dominance of continuum and electron Landau damping in this case. Similar experimental and computational studies are planned for the recent hydrogen and ongoing tritium campaigns, in preparation for the upcoming DT campaign. Submitted for publication in Nuclear Fusion

Measuring stopping power in warm dense matter plasmas at OMEGA

2025-04-08T04:24:25Z

Measuring stopping power in warm dense matter plasmas at OMEGA Lahmann, Brandon; Saunders, A.M.; Döppner, T.; Frenje, Johan A.; Glenzer, S.H.; Gatu Johnson, Maria; Sutcliffe, G.; Zylstra, A.B.; Petrasso, Richard D. A platform has been developed for accurately measuring the stopping power of high energy protons through warm dense matter (WDM) plasmas characterized by x-ray Thomson scattering. In this work stopping power measurements were successfully made through both WDM Beryllium and Boron plasmas. In the Boron experiments, an increase in stopping was observed over their cold target counter-parts. This increase in stopping was shown to agree well with models that account for the partial ionization of the plasma. Submitted for publication in Plasma Physics and Controlled Fusion

Microwave diagnostics damage by parametric decay instabilities during electron cyclotron resonance heating in ASDEX Upgrade

2025-04-08T04:32:43Z

Microwave diagnostics damage by parametric decay instabilities during electron cyclotron resonance heating in ASDEX Upgrade Hansen, Soren K.; Jacobsen, A.S.; Willensdorfer, M.; Nielsen, S.K.; Stober, J.; Hofler, K.; Maraschek, M.; Fischer, R.; Dunne, M. We present observations of microwave diagnostics damage in three discharges employing third-harmonic X-mode electron cylcotron resonance heating (ECRH) at the ASDEX Upgrade tokamak. In all cases, the diagnostics damage is explainable in terms of a parametric decay instability (PDI), where an X-mode ECRH wave decays to two trapped upper hybrid (UH) waves near half the ECRH frequency, followed by secondary instabilities, which generate strong microwave signals near multiples of half the ECRH frequency that cause the damage. Trapping of the UH waves near half the ECRH frequency is necessary to reduce the ECRH power required for exciting the PDIs to a level attainable at ASDEX Upgrade, and may occur when the second-harmonic UH resonance of the ECRH waves is present in a region of non-monotonic electron density, e.g. near the O-point of a magnetohydrodynamic mode or the plasma center. The diagnostics damage in the three discharges may be attributed to PDIs occurring near the O-point of a rotating mode, near the plasma center, and near the O-point of a locked mode, respectively. In the rotating mode case, the strong signals are shown to be quasi-periodic, with spikes occurring when the O-point of the mode passes through an ECRH beam, as expected. In the locked mode case, Thomson scattering profiles demonstrate the possibility of the primary PDI occurring based on experimental data for the first time under fusion-relevant conditions. Applying the framework used for ASDEX Upgrade to the X-mode ECRH scenarios planned for the early operation phase of ITER, the PDIs are found to be likely in connection with 170 GHz ECRH of half field scenarios and 104 GHz (or 110 GHz) ECRH of one third field scenarios. Finally, several strategies for mitigating diagnostics damage are proposed. Submitted for publication in Plasma Physics and Controlled Fusion

The crucial role of diagnostics in achieving ignition on the National Ignition Facility (NIF)

2025-04-07T08:27:09Z

The crucial role of diagnostics in achieving ignition on the National Ignition Facility (NIF) Kilkenny, J.D.; Batha, S.H.; Pak, A.; Landen, O.L.; Bradley, D.K.; Moore, A.S.; Gatu Johnson, Maria; Meezan, N.B.; Mackinnon, A.J.; Haan, S.W.; Regan, S.P.; Hsing, W.W.; Smalyul, V.A. Well over 100 diagnostics can operate on the National Ignition Facility (NIF) as a result of several decades of development on NIF, and before that on Nova, OMEGA, and earlier LLNL lasers. A subset of these have guided the approach to achieving ignition on the NIF in 2022 [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129(7), 075001 (2022)]. Achieving ignition on NIF has required many types of experiments with this core set of diagnostics, some constraining known unknowns and some revealing surprises—arguably unknown unknowns. Early design work realized that the extreme precision required for ignition on NIF would require fine-tuning by experiment, that is, measuring and adjusting known unknowns. Many examples are given where the use of the core set of ignition diagnostics in experimental arrangements called platforms demonstrated control of the key theoretical parameters defined as shape, adiabat, velocity, and mix. The direction of the adjustments to input conditions is found either by trend analysis or, in many cases, by observing from the diagnostic data the direction to make an adjustment. In addition, diagnostics have revealed some unexpected or neglected known issues, which degrade performance, or unexpected issues, unknown unknowns. Some of these factors had been previously considered, but underestimated or difficult to calculate at the time. The overall methodology can be described as a variant of Popper’s falsifiability philosophy [K. Popper, The Logic of Scientific Discovery (Hutchinson, 1974)]. This paper summarizes the role of ignition diagnostics in terms of falsification or validation of theory or experimental setup as well as uncovering unexpected issues. The journey to ignition started in the seventies with a 1-mm wavelength laser producing disastrous results. Diagnostics have guided us to the recent multi-decadal goal of demonstrating ignition and burn in the laboratory. Submitted for publication in Physics of Plasmas

Isotope effects on energy transport in the core of ASDEX-Upgrade tokamak plasmas: Turbulence measurements and model validation

2025-04-07T09:23:35Z

Isotope effects on energy transport in the core of ASDEX-Upgrade tokamak plasmas: Turbulence measurements and model validation Molina Cabrera, Pedro A.; Rodriguez Fernandez, Pablo; Görler, T.; Bergmann, M.; Höfler, K.; Denk, S.S.; Bielajew, R.; Conway, G.D.; Yoo, C.; White, Anne E.; ASDEX Upgrade Team Design and operation of future tokamak fusion reactors using a deuterium-tritium 50:50 mix requires a solid under- standing of how energy confinement properties change with ion mass. This study looks at how turbulence and energy transport change in L-mode plasmas in the ASDEX Upgrade tokamak when changing ion species between hydrogen and deuterium. For this purpose, both experimental turbulence measurements and modeling are employed. Local mea- surements of ion-scale (with wavevector of fluctuations perpendicular to the B-field k⊥ <2 cm−1, k⊥ρs <0.2 , where ρs is the ion sound Larmor radius using the deuterium ion mass) electron temperature fluctuations have been performed in the outer core (normalized toroidal flux ρTor = 0.65 − 0.8) using a multi-channel correlation electron cyclotron emission diagnostic (CECE). Lower root-mean-square perpendicular fluctuation amplitudes and radial correlation lengths have been measured in hydrogen versus deuterium. Measurements of the cross-phase angle between a normal-incidence re- flectometer and an ECE signal were made to infer the cross-phase angle between density and temperature fluctuations. The magnitude of the cross-phase angle was found larger (more out-of-phase) in hydrogen than in deuterium. TRANSP power balance simulations show a larger ion heat flux in hydrogen where the electron-ion heat exchange term is found to play an important role. These experimental observations were used as the basis of a validation study of both quasi- linear gyrofluid TGLF-SAT2 and nonlinear gyrokinetic GENE codes. Linear solvers indicate that, at long wavelengths (k⊥ρs < 1), energy transport in the deuterium discharge is dominated by a mixed ion-temperature-gradient (ITG) and trapped-electron mode (TEM) turbulence while in hydrogen transport is exclusively and more strongly driven by ITG turbulence. The Ricci validation metric has been used to quantify the agreement between experiments and simulations taking into account both experimental and simulation uncertainties as well as up to five different observables accross different levels of the primacy hierarchy. Submitted for publication in Physics of Plasmas

Hydroscaling indirect-drive implosions on the National Ignition Facility

2025-04-08T04:16:45Z

Hydroscaling indirect-drive implosions on the National Ignition Facility Baker, K.L.; Jones, O.; Weber, C.; Clark, D.; Patel, P.K.; Thomas, C.A.; Landen, O.L.; Nora, R.; Anderson, G.J.; Gaffney, J.; MacLaren, S.; Casey, D.T.; Döppner, T.; Dewald, E.; Tommasini, R.; Spears, B.K.; Salmonson, J.; Hohenberger, M.; Khan, S.; Zylstra, A.; Kritcher, A.; Amendt, P.; Smalyuk, V.; Lindl, J.; Young, C.; Ross, S.; Ho, D.; Hurricane, O.A.; Callahan, D.A.; Woods, T.; Milovich, J.L.; Berger, R.L.; Strozzi, D.; Bachmann, B.; Bionta, R.; Celliers, P.M.; Fittinghoff, D.; Hatarik, R.; Gatu Johnson, Maria; Meaney, K.; Millot, M.; Volegov, P.L.; Wilde, C. A goal of the laser-based National Ignition Facility (NIF) is to increase the liberated fusion energy “yield” in inertial confinement fusion experiments well past the ignition threshold and the input laser energy. One method of increasing the yield, hydrodynamic scaling of current experiments, does not rely on improving compression or implosion velocity, but rather increases the scale of the implosion to increase hotspot areal density and confinement time. Indirect-drive (Hohlraum driven) implosions carried out at two target sizes, 12.5% apart, have validated hydroscaling expectations. Moreover, extending comparisons to the best-performing implosions at five different capsule sizes shows that their performance also agrees well with hydroscaling expectations even though not direct hydroscales of one another. In the future, by switching to a reduced loss Hohlraum geometry, simulations indicate that we can drive 20% larger-scale implosions within the current power and energy limitations on the NIF. At the demonstrated compression and velocity of these smaller-scale implosions, these 1.2 hydroscaled implosions should put us well past the ignition threshold. Submitted for publication in Physics of Plasmas

Enhanced Laser–Energy Coupling with Small-Spot Distributed Phase Plates (SG5-650) in OMEGA DT Cryogenic Target Implosions

2025-04-07T08:41:21Z

Enhanced Laser–Energy Coupling with Small-Spot Distributed Phase Plates (SG5-650) in OMEGA DT Cryogenic Target Implosions Theobald, W.; Cao, D.; Shah, R.C.; Thomas, C.A.; Igumenshchev, I.V.; Bauer, K.A.; Betti, R.; Bonino, M.J.; Campbell, E.M.; Christopherson, A.R.; Churnetski, K.; Edgell, D.H.; Forrest, C.J.; Frenje, Johan A.; Gatu Johnson, Maria; Glebov, V.Yu.; Goncharov, V.N.; Gopalaswamy, V.; Harding, D.R.; Hu, S.X.; Ivancic, S.T.; Jacobs-Perkins, D.W.; Janezic, R.T.; Joshi, T.; Knauer, J.P.; Lees, A.; Luo, R.W.; Mannion, O.M.; Marshall, F.J.; Mohamed, Z.L.; Morse, S.F.B.; Patel, D.; Peebles, J.L.; Petrasso, Richard D.; Radha, P.B.; Rinderknecht, H.G.; Rosenberg, M.J.; Sampat, S.; Sangster, T.C.; Shmayda, W.T.; Shuldberg, C.M.; Shvydky, A.; Sorce, C.; Stoeckl, C.; Wittman, M.D.; Regan, S.P. Cryogenic deuterium–tritium ice target implosions on OMEGA with new small-spot ("SG5-650") distributed phase plates (DPP's) achieved an (11 +/- 4)% increase in energy coupling compared to implosions with standard-spot DPP's by decreasing the ratio of the laser spot diameter to the target diameter from 0.93 to 0.75. The SG5-650 DPP's provide a focus spot size of 674 um, which is defi ned as the diameter that encircles 95% of the measured beam energy compared to 834 um for the SG5-850. The hydrodynamic effciency, defi ned as the ratio of the kinetic energy in the imploding shell to the laser energy, increased from 4.5% to 5.0% based on radiation-hydrodynamic calculations benchmarked to shell trajectory and bang-time measurements. The higher coupling came with a trade-off of an increased hot-electron production as well as increased hydrodynamic instabilities seeded by a larger mode-10 amplitude from the beam port geometry, both of which may have affected the fusion neutron production and areal density. Submitted for publication in Physics of Plasmas

Modeling the spectral modification of lower hybrid wave in the presence of drift-wave type density fluctuation in the scrape-off-layer of the EAST tokamak

2025-04-07T09:14:35Z

Modeling the spectral modification of lower hybrid wave in the presence of drift-wave type density fluctuation in the scrape-off-layer of the EAST tokamak Wu, C.B.; Ding, B.J.; Li, M.H.; Baek, Seung Gyou; Wallace, Greg M.; Li, Y.C.; Yan, G.H. The spectrum change of lower hybrid (LH) waves caused by low-frequency density fluctuation in the scrape-off layer (SOL) is studied by applying the wave scattering model developed by Bonoli and Ott [Bonoli and Ott, Physics of Fluids 25, 359 (1982)] via a Monte Carlo method. Due to the influence of density fluctuation, the perpendicular component of the LH wave-vector can be rotated in the 2D perpendicular space, which will further change the ray trajectory of the LH wave. A ray-tracing model specific to this purpose is developed to evaluate the probability distribution of both poloidal refractive index (N_theta) and the parallel refractive index (n||) of the LH wave at the last closed flux surface (LCFS), assuming wave propagation through the turbulent SOL plasma from the launcher at the far SOL to the LCFS. In the presence of the drift-wave-type density fluctuations, the Monte-Carlo approach is adopted to characterize the scattering probability and the scattering angle of the perpendicular LH wave-vector. The scattering probability and the rotation angle are determined by the combined effect from the geometric optics approximation term and the E×B drift term in the LH tensor elements. The probability distributions of N|| and N_theta at the LCFS are studied using the EAST parameters as a function of wave frequency, the initial n||, and the polar injection position, which may influence the LHCD efficiency. Submitted for publication in Physics of Plasmas

Turbulent field fluctuations in gyrokinetic and fluid plasmas

2025-04-07T08:50:55Z

Turbulent field fluctuations in gyrokinetic and fluid plasmas Mathews, Abhilash; Mandell, N.; Francisquez, M.; Hughes, Jerry W.; Hakim, A. A key uncertainty in the design and development of magnetic confinement fusion energy reactors is predicting edge plasma turbulence. An essential step in overcoming this uncertainty is the validation in accuracy of reduced turbulent transport models. Drift-reduced Braginskii two-fluid theory is one such set of reduced equations that has for decades simulated boundary plasmas in experiment, but significant questions exist regarding its predictive ability. To this end, using a novel physics-informed deep learning framework, we demonstrate the first ever direct quantitative comparisons of turbulent field fluctuations between electrostatic two-fluid theory and electromagnetic gyrokinetic modelling with good overall agreement found in magnetized helical plasmas at low normalized pressure. This framework is readily adaptable to experimental and astrophysical environments, and presents a new technique for the numerical validation and discovery of reduced global plasma turbulence models. Submitted for publication in Physics of Plasmas

Mildly relativistic collisionless shock formed by magnetic piston

2025-04-07T08:31:47Z

Mildly relativistic collisionless shock formed by magnetic piston Moreno, Q.; Araudo, A.; Korneev, Ph.; Li, Chi-Kang; Tikhonchuk, V.T.; Ribeyre, X.; d'Humieres, E.; Weber, S. By using particle-in-cell simulations, we study the collision of two plasma flows with one of them carrying a magnetic field. Ion interpenetration results in the formation of a magnetic piston with the magnetic field compression proportional to the density ratio of the colliding plasmas. The counterpropagating ions in the nonmagnetized plasma upstream from the piston excite the ion Weibel instability, which turns into magnetic turbulence. The thickness of the piston increases with time, and it turns into a reverse magnetized shock after less than one ion gyro period. In front of the piston, the time needed to decrease the nonmagnetized ion anisotropy using the magnetic turbulence is much larger than the ion gyroperiod in the piston. Consequently, particles are reflected by the piston, which acts as a wall initiating a transient phase. After several ion periods, the formation of this electromagnetic forward shock is, then, accelerated by the piston, and at large timescale, the dissipation of energy is eventually mediated only by the Weibel turbulence. We report here a new configuration of shocks, where a reverse magnetized and a forward electromagnetic shock coexist separated by a tangential discontinuity. Particle acceleration and heating in the two shock structures and relevance of this scenario of collisionless shock formation to laboratory experiments and astrophysical conditions are discussed. Submitted for publication in Physics of Plasmas

Principal factors in performance of indirect-drive laser fusion experiments

2025-04-08T04:44:23Z

Principal factors in performance of indirect-drive laser fusion experiments Thomas, C.A.; Campbell, E.M.; Baker, K.L.; Casey, D.T.; Hohenberger, M.; Kritcher, A.L.; Spears, B.K.; Khan, S.F.; Nora, R.; Woods, D.T.; Milovich, J.L.; Berger, R.L.; Strozzi, D.; Ho, D.D.; Clark, D.; Bachmann, B.; Benedetti, L.R.; Bionta, R.; Celliers, P.M.; Fittinghoff, D.N.; Grim, G.; Hatarik, R.; Izumi, N.; Kyrala, G.; Ma, T.; Millot, M.; Nagel, S.R.; Patel, P.K.; Yeamans, C.; Nikroo, A.; Tabak, M.; Gatu Johnson, Maria; Volegov, P.L.; Finnegan, S.M. Progress in inertial confinement fusion depends on the accurate interpretation of experiments that are complex and difficult to explain with simulations. Results could depend on small changes in the laser pulse or target or physics that are not fully understood or characterized. In this paper we discuss an x-ray-driven platform [K. Baker et al., Phys. Rev. Lett. 121, 135001 (2018)] with fewer sources of degradation, and find the fusion yield can be described as a physically motivated function of laser energy, target scale, and implosion symmetry. This platform and analysis could enable a more experimental approach to the study and optimization of implosion physics. Submitted for publication in Physics of Plasmas

Disruption halo current rotation scaling on Alcator C-Mod and HBT-EP

2025-04-08T04:35:17Z

Disruption halo current rotation scaling on Alcator C-Mod and HBT-EP Saperstein, Alex R.; Tinguely, R. Alex; Granetz, R.S.; Levesque, J.P.; Maue, M.E.; Navrati, G.A. Asymmetric halo currents (HCs) can exert large net forces on the vacuum vessel and other components during disruptions on tokamaks. The displacements caused by these forces can then be amplified if these asymmetric forces rotate at frequencies resonant with the vessel. This paper reports on the investigation of a recently proposed scaling law for the disruption HC rotation frequency that combines measurements on Alcator C-Mod with those on HBT-EP. We find that a new non-circular version of the scaling law ( *m/ \propto 1 B*T*(S/pi) ) takes into consideration the dependence of f_rot on the poloidal structure of the MHD instability (m) driving the asymmetry and describes the disruption-averaged rotation frequency on C-Mod. Disruption rotation is also found to be insensitive to the vertical position and impurity content of the plasma at the onset of the disruption.However, a stagnation in the time-evolution of f_rot is occasionally observed. Observations are consistent with the dominance of poloidal rotation during the disruption, which is motivated by the poloidal drift nature of the scaling law. Submitted for publication in Physics of Plasmas

Reaching a Burning Plasma and Ignition Using Smaller Capsules/Hohlraums, Higher Radiation Temperatures and Thicker Ablator/Ice on the National Ignition Facility

2025-04-07T08:40:42Z

Reaching a Burning Plasma and Ignition Using Smaller Capsules/Hohlraums, Higher Radiation Temperatures and Thicker Ablator/Ice on the National Ignition Facility Baker, K.L.; Thomas, C.A.; Landen, O.L.; Haan, S.; Lindl, J.D.; Casey, D.T.; Young, C.; Nora, R.; Hurricane, O.A.; Callahan, D.A.; Jones, O.; Berzak Hopkins, L.; Khan, S.; Spears, B.K.; Le Pape, S.; Meezan, N.B.; Ho, D.D.; Döppner, T.; Hinkel, D.; Dewald, E.L.; Tommasini, R.; Hohenberger, M.; Weber, C.; Clark, D.; Woods, D.T.; Milovich, J.L.; Strozzi, D.; Kritcher, A.; Robery, H.F.; Ross, J.S.; Smalyuk, V.A.; Amendt, P.A.; Bachmann, B.; Benedetti, L.R.; Bionta, R.; Celliers, P.M.; Fittinghoff, D.; Goyon, C.; Hatarik, R.; Izumi, N.; Gatu Johnson, Maria; Kyrala, G.; Ma, T.; Meaney, K.; Millot, M.; Nagel, S.R.; Patel, P.K.; Turnbell, D.; Volegov, P.L.; Yeamans, C.; Wilde, C. In indirect-drive implosions, the final core hot spot energy and pressure and hence neutron yield attainable in 1D increases with increasing laser peak power and hence radiation drive temperature at fixed capsule and hohlraum size. We present simple analytic scalings validated by 1D simulations that quantify the improvement in performance and use this to explain existing data and simulation trends. Extrapolating to the 500 TW NIF peak power limit in a low gas-fill 5.4 mm diameter hohlraum based on existing high adiabat implosion data at 400 TW, 1.3 MJ and 1e16 yield, we find that a 2-3e17 yield (0.5 – 0.7 MJ) is plausible using only 1.8 MJ of laser energy. Based on existing data varying DT fuel thickness and dopant areal density, further improvements should be possible by increasing DT fuel areal density, and hence confinement time and yield amplification. Submitted for publication in Physics of Plasmas

The role of toroidal rotation in the very high energy confinement quality observed in super H-mode experiments on DIII-D

2025-04-07T08:36:33Z

The role of toroidal rotation in the very high energy confinement quality observed in super H-mode experiments on DIII-D Ding, S.; Garofalo, A.M.; Jian, X.; Holland, C.; Grierson, B.A.; Soloman, W.M.; Marinoni, Alessandro; Knolker, M.; McClenaghan, J. In this paper, we report the key role that toroidal rotation and the related ExB shear physics played in the very high energy confinement quality (H98y2>1.5) of super H-mode experiments on DIII-D. Experiments show that the energy confinement quality decreases when toroidal rotation decreases due to the decreased externally controlled torque per particle. Meanwhile, the total pedestal pressure in the experiments remains very high during the rotation and confinement quality change. TGYRO transport modeling suggests the contribution from rotation in the ExB shear is responsible for the confinement quality in excess of standard H-mode (H98y2~1). CGYRO gyrokinetic simulations reveal the governing physics in the core plasma of super H-modes: significant up-shift of nonlinear the ITG critical gradient is observed when applying ExB shear physics in the modeling based on experimental data. The effects of other physical parameters and contribution from pedestal height, which may play minor roles in this study, are also discussed. Submitted for publication in Physics of Plasmas

Experimental observations of detached bow shock formation in the interaction of a laser-produced plasma with a magnetized obstacle

2025-04-08T04:21:42Z

Experimental observations of detached bow shock formation in the interaction of a laser-produced plasma with a magnetized obstacle Levesque, Joseph M.; Liao, Andy S.; Hartigan, Patrick; Young, Rachel P.; Trantham, Matthews; Gray, Williams; Klein, Sallee; Manuel, Mario; Fiksel, Gennady; Katz, Joseph; Li, Chi-Kang; Birkel, Andrew; Tzeferacos, Petros; Kuranz, Carolyn C. The magnetic field produced by planets with active dynamos, like the Earth, can exert sufficient pressure to oppose supersonic stellar wind plasmas, leading to the formation of a standing bow shock upstream of the magnetopause, or pressure-balance surface. Scaled laboratory experiments studying the interaction of an inflowing solar wind analog with a strong, external magnetic field are a promising new way to study magnetospheric physics and to complement existing models, although reaching regimes favorable for magnetized shock formation is experimentally challenging. This paper presents experimental evidence of the formation of a magnetized bow shock in the interaction of a supersonic, super-Alfvenic plasma with a strongly magnetized obstacle at the OMEGA laser facility. The solar wind analog is generated by the collision and subsequent expansion of two counter- propagating, laser-driven plasma plumes. The magnetized obstacle is a thin wire, driven with strong electrical currents. Hydrodynamic simulations using the FLASH code predict that the colliding plasma source meets the criteria for bow shock formation. Spatially resolved, optical Thomson scat- tering measures the electron number density, and optical emission lines provide a measurement of the plasma temperature, from which we infer the presence of a fast magnetosonic shock far upstream of the obstacle. Proton images provide a measure of large-scale features in the magnetic field topology, and reconstructed path-integrated magnetic field maps from these images suggest the formation of a bow shock upstream of the wire and as a transient magnetopause. We compare features in the reconstructed fields to two-dimensional MHD simulations of the system. Submitted for publication in Physics of Plasmas

Effect of cross-beam energy transfer on target-offset asymmetry in direct-drive inertial confinement fusion implosions

2025-04-08T04:11:34Z

Effect of cross-beam energy transfer on target-offset asymmetry in direct-drive inertial confinement fusion implosions Anderson, K.S.; Forrest, C.J.; Mannion, O.M.; Marshall, F.J.; Shah, R.C.; Michel, D.T.; Marozas, J.A.; Radha, P.B.; Edgell, D.H.; Epstein, R.; Goncharov, V.N.; Knauer, J.P.; Gatu Johnson, Maria; Laffite, S. The unintentional mispositioning of inertial confinement fusion (ICF) capsules from the center of laser beam convergence has long been shown in simulations to generate large ℓ = 1 asymmetry and significantly degrade implosion symmetry and fusion yields. Experimental yields on the OMEGA Laser System, however, have shown much less sensitivity to this initial target offset. This paper presents simulations of offset ICF implosions improved by including a physics model of cross-beam energy transfer (CBET), a mechanism of laser energy scattering from one beam to another. Room-temperature OMEGA implosion experiments with prescribed target offsets are simulated with and without CBET, illustrating that CBET mitigates the ℓ = 1 implosion asymmetry from target offset. Comparison of simulations to multiple complementary experimental observables indicates the addition of CBET physics in offset simulations is necessary to match experimental results. Submitted for publication in Physics of Plasmas

A second order yield-temperature relation for accurate inference of burn-averaged quantities in multi-species plasmas

2025-04-07T09:16:35Z

A second order yield-temperature relation for accurate inference of burn-averaged quantities in multi-species plasmas Kabadi, Neel V.; Adrian, Patrick J.; Bose, A.; Casey, D.T.; Frenje, Johan A.; Gatu Johnson, Maria; Lahmann, Brandon; Mannion, O.M.; Petrasso, Rrichard D.; Rinderknecht, H.G.; Séguin, Frederick H.; Sio, H.W.; Sutcliffe, G.D.; Zylstra, A.B. Measured yields and ion temperatures inferred from the fusion product energy spectra can be used as metrics for the performance of an ICF implosion. This can be to infer species separation, thermal decoupling, flows or other effects that can cause the inferred ion temperatures to deviate from the true underlying thermal temperature and the yield ratio to deviate from the expected value. Direct inference of the impact of these effects on observed temperatures and yields can be difficult to uncover due to underlying dependence on the shape and time evolution of the temperature and density pro les of the fusing plasma. Due to differences in the temperature dependence of the reactivities, different fusion products are emitted from different regions and times within the implosion. In order to properly account for this, a second order analytic expression relating the apparent temperatures and yield ratios is developed. This expression can be coupled to models of yield and/or temperature altering effects to infer their burn-averaged impact on an implosion. The second order expression shows significant improvement over lower order expressions in synthetic data studies. Demonstrations of its applications to synthetic data coupled with models of ion thermal decoupling and radial flows are presented. In the case of thermal decoupling both first and second order expressions show reasonable levels of accuracy. To consistently infer the amplitude of radial flow with <10% error the second order equation is required. Submitted for publication in Physics of Plasmas

Laser-direct-drive fusion target design with a high-Z gradient-density pusher shell

2025-04-07T09:12:52Z

Laser-direct-drive fusion target design with a high-Z gradient-density pusher shell Hu, S.X.; Ceurvorst, L.; Peebles, J.L.; Mao, A.; Li, P.; Lu, Y.; Shvydky, A.; Goncharov, V.N.; Epstein, R.; Nichols, K.; Goshadze, R.M.N.; Ghosh, M.; Hinz, J.; Karasiev, V.V.; Zhang, S.; Shaffer, N.R.; Mihaylov, D.I.; Cappelletti, J.; Harding, D.R.; Li, Chi-Kang; Campbell, E.M.; Shah, R.C.; Collins, T.J.B.; Regan, S.P.; Deeney, C. Laser-direct-drive fusion target designs with solid deuterium-tritium (DT) fuel, a high-Z gradient-density pusher shell (GDPS), and a Au-coated foam layer have been investigated through both 1D and 2D radiationhydrodynamic simulations. Compared with conventional low-Z ablators and DT-push-on-DT targets, these GDPS targets possess certain advantages of being instability-resistant implosions that can be high adiabat (α 8) and low hot-spot and pusher-shell convergence (CRhs ≈ 22 and CRPS ≈ 17), and have a low implosion velocity (vimp < 3 × 107 cm/s). Using symmetric drive with laser energies of 1.9 to 2.5 MJ, 1D LILAC simulations of these GDPS implosions can result in neutron yields corresponding to 50−MJ energy, even with reduced laser absorption due to the cross-beam energy transfer (CBET) effect. Two-dimensional DRACO simulations show that these GDPS targets can still ignite and deliver neutron yields from 4 to ∼10 MJ even if CBET is present, while traditional DT-push-on-DT targets normally fail due to the CBET-induced reduction of ablation pressure. If CBET is mitigated, these GDPS targets are expected to produce neutron yields of >20 MJ at a driven laser energy of ∼2 MJ. The key factors behind the robust ignition and moderate energy gain of such GDPS implosions are as follows: (1) The high initial density of the high-Z pusher shell can be placed at a very high adiabat while the DT fuel is maintained at a relatively low-entropy state; therefore, such implosions can still provide enough compression ρR >1 g/cm2 for sufficient confinement; (2) the high-Z layer significantly reduces heat-conduction loss from the hot spot since thermal conductivity scales as ∼1/Z; and (3) possible radiation trapping may offer an additional advantage for reducing energy loss from such high-Z targets. Submitted for publication in Physical Review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics

Direct Measurements of DT Fuel Preheat from Hot Electrons in Direct-Drive Inertial Confinement Fusion

2025-04-07T08:55:02Z

Direct Measurements of DT Fuel Preheat from Hot Electrons in Direct-Drive Inertial Confinement Fusion Christopherson, A.R.; Betti, R.; Forrest, C.J.; Howard, J.; Theobald, W.; Delettrez, J.A.; Rosenberg, M.J.; Solodov, A.A.; Stoeckl, C.; Patel, D.; Gopalaswamy, V.; Cao, D.; Peebles, J.L.; Edgell, D.H.; Seka, W.; Epstein, R.; Wei, M.S.; Gatu Johnson, Maria; Simpson, R.; Regan, S.P.; Campbell, E.M. Hot electrons generated by laser-plasma instabilities degrade the performance of laser-fusion implosions by preheating the DT fuel and reducing core compression. The hot-electron energy deposition in the DT fuel has been directly measured for the first time by comparing the hard x-ray signals between DT-layered and mass-equivalent ablator-only implosions. The electron energy deposition profile in the fuel is inferred through dedicated experiments using Cu-doped payloads of varying thickness. The measured preheat energy accurately explains the areal-density degradation observed in many OMEGA implosions. This technique can be used to assess the viability of the direct-drive approach to laser fusion with respect to the scaling of hot-electron preheat with laser energy. Submitted for publication in Physical Review Letters

Weakly Magnetized, Hall Dominated Plasma Couette Flow

2025-04-08T04:30:12Z

Weakly Magnetized, Hall Dominated Plasma Couette Flow Flanagan, K.; Milhone, J.; Egedal, J.; Endrizzi, D.; Olson, J.; Peterson, Ethan E.; Sassella, R.; Forest, C.B. A novel plasma equilibrium in the high-β, Hall regime that produces centrally-peaked, high Mach number Couette flow is described. Flow is driven using a weak, uniform magnetic field and large, cross field currents. Large magnetic field amplification (factor 20) due to the Hall effect is observed when electrons are flowing radially inward, and near perfect field expulsion is observed when the flow is reversed. A dynamic equilibrium is reached between the amplified (removed) field and extended density gradients. Submitted for publication in Physical Review Letters

Design of an inertial fusion experiment exceeding the Lawson criterion for ignition

2025-04-08T04:21:30Z

Design of an inertial fusion experiment exceeding the Lawson criterion for ignition Kritcher, A.L.; Zylstra, A.B.; Callahan, D.A.; Hurricane, O.A.; Weber, C.R.; Clark, D.S.; Young, C.V; Ralph, J.E.; Casey, D.T.; Pak, A.; Landen, O.L.; Bachmann, B.; Baker, K.L.; Berzak Hopkins, L.; Bhandarkar, S.D.; Biener, J.; Bionta, R.M.; Birge, N.W.; Braun, T.; Briggs, T.M.; Celliers, P.M.; Chen, H.; Choate, C.; Divol, L.; Döppner, T.; Fittinghoff, D.; Edwards, M.J.; Gatu Johnson, Maria; Gharibyan, N.; Haan, S.; Hahn, K.D.; Hartouni, E.; Hinkel, D.E.; Ho, D.D.; Hohenberger, M.; Holder, J.P.; Huang, H.; Izumi, N.; Jeet, J.; Jones, O.; Kerr, S.M.; Khan, S.F.; Geppert Kleinrath, H.; Geppert Kleinrath, V.; Kong, C.; Lamb, K.M.; Le Pape, S.; Lemos, N.C.; Lindl, J.D.; MacGowan, B.J.; Mackinnon, A.J.; MacPhee, A.G.; Marley, E.V.; Meaney, K.; Millot, M.; Moore, A.S.; Newman, K.; Di Nicola, J.-M. G.; Nikroo, A.; Nora, R.; Patel, P.K.; Rice, N.G.; Rubery, M.S.; Sater, J.; Schlossberg, D.J.; Sepke, S.M.; Sequoia, K.; Shin, S.J.; Stadermann, M.; Stoupin, S.; Strozzi, D.J.; Thomas, C.A.; Tommasini, R.; Trosseille, C.; Tubman, E.R.; Volegov, P.L.; Wild, C.; Woods, D.T.; Yang, S.T. We present the design of the first igniting fusion plasma in the laboratory by Lawson’s criterion that produced 1.37 MJ of fusion energy, Hybrid-E experiment N210808 (August 8, 2021) [Phys. Rev. Lett. 129, 075001 (2022)]. This design uses the indirect drive inertial confinement fusion approach to heat and compress a central “hot spot” of deuterium-tritium (DT) fuel using a surrounding dense DT fuel piston. Ignition occurs when the heating from absorption of α particles created in the fusion process overcomes the loss mechanisms in the system for a duration of time. This letter describes key design changes which enabled a ∼3–6× increase in an ignition figure of merit (generalized Lawson criterion) [Phys. Plasmas 28, 022704 (2021), Phys. Plasmas 25, 122704 (2018)]) and an eightfold increase in fusion energy output compared to predecessor experiments. We present simulations of the hot-spot conditions for experiment N210808 that show fundamentally different behavior compared to predecessor experiments and simulated metrics that are consistent with N210808 reaching for the first time in the laboratory “ignition.” Submitted for publication in Physical Review E

Hotspot Parameter Scaling with Velocity and Yield for High Adiabat Layered Implosions on the National Ignition Facility

2025-04-07T09:25:44Z

Hotspot Parameter Scaling with Velocity and Yield for High Adiabat Layered Implosions on the National Ignition Facility Baker, K.L.; Thomas, C.A.; Casey, D.T.; Hohenberger, M.; Khan, S.; Spears, B.K.; Landen, O.L.; Nora, R.; Woods, T.; Milovich, J.L.; Berger, R.L.; Strozzi, D.; Weber, C.; Clark, D.; Hurricane, O.A.; Callahan, D.A.; Kritcher, A.; Bachmann, B.; Benedetti, R.; Bionta, R.; Celliers, P.M.; Fittinghoff, D.; Goyon, C.; Hatarik, R.; Izumi, N.; Gatu Johnson, Maria; Kyrala, G.; Ma, T.; Meaney, K.; Millot, M.; Nagel, S.R.; Patel, P.K.; Turnbull, D.; Volegov, P.L.; Yeamans, C.; Wilde, C. This paper presents a study on hotspot parameters in indirect-drive inertially confined fusion implosions as they proceed through the self-heating regime. The implosions with increasing nuclear yield would reach the burning plasma regime, hotspot ignition and finally propagating burn and ignition. These implosions span a wide range of alpha heating from a yield amplification of 1.7 to 2.5. We show that the hotspot parameters are explicitly dependent on both yield and velocity and that by fitting to both of these quantities the hotspot parameters can be fit with a single power law in velocity. The yield scaling also enables the hotspot parameters extrapolation to higher yields. This is important as various degradation mechanisms can occur on a given implosion at fixed implosion velocity which can have a large impact on both yield and the hotspot parameters. The yield scaling also enables the experimental dependence of the hotspot parameters on yield amplification to be determined. The implosions reported have resulted in the highest yield(1.73x10^16+/-2.6%), yield amplification, pressure and implosion velocity yet reported on the National Ignition Facility. Submitted for publication in Physical Review E

Argon Pumpout by ICRF Waves in C-Mod L- and I-mode Plasmas

2025-04-08T04:31:00Z

Argon Pumpout by ICRF Waves in C-Mod L- and I-mode Plasmas Rice, John E.; Lin, Y.; Perks, C.J.; Reinke, M.L.; Marmar, E.S.; Cao, N.; Gao, C.; Sciortino, Francesco; Wukitch, S.J.; Wright, John C. Pumpout of argon ions by ICRF waves has been observed in C-Mod deuterium L- and I-mode plasmas that had a substantial hydrogen fraction. The effect is manifested by a reduction of core argon x-ray brightness up to a factor of 90% on time scales of tens of milliseconds following injection of ICRF power. For Ar^16+, the pumpout is strongest for hydrogen minority concentrations between 0.25 and 0.4, when the ICRF waves are not expected to result in minority heating. Modeling with the TORIC code suggests that the pumpout process occurs when the H/D mode conversion layer overlaps with the 2nd harmonic impurity resonance layer. The magnitude of the argon pumpout is independent of ICRF power above an apparent threshold of ~500 kW, independent of electron density and appears to decrease as the plasma current is increased. Potential application as a heavy impurity control tool in reactors is discussed. Submitted for publication in Nuclear Fusion

Creation and sustainment of wide pedestal quiescent H-mode with zero net neutral beam torque

2025-04-07T08:25:56Z

Creation and sustainment of wide pedestal quiescent H-mode with zero net neutral beam torque Burrell, K.H.; Chen, Xi; Chrystal, C.; Ernst, Darin R.; Grierson, B.A.; Haskey, S.R.; Osborne, T.H.; Paz-Soldan, C.; Wilks, Theresa M. Recent experiments on DIII-D have shown it is possible to create and sustain wide pedestal quiescent H-mode (QH-mode) plasmas with zero net torque from neutral beam injection (NBI) for the full discharge duration. Wide pedestal QH-mode has many of the features of the previously investigated QH-mode while having the advantage of increased edge pedestal pressure and excellent energy confinement time. Both QH-mode variants operate without edge localized modes. Accordingly, these new discharges demonstrate that significant input torque is not essential to the exploitation of wide pedestal QH-mode in future devices that are expected to have small or non-existent NBI torque. Developing operating conditions that allowed net zero torque access to wide pedestal QH-mode required implementing several techniques to avoid locked modes including minimizing intrinsic error fields, avoiding large sawteeth, and driving toroidal rotation via neoclassical toroidal viscosity. Submitted for publication in Nuclear Fusion

Evidence for suprathermal ion distribution in burning plasmas

2025-04-07T08:24:52Z

Evidence for suprathermal ion distribution in burning plasmas Hartouni, E.P.; Moore, A.S.; Crilly, A.J.; Appelbe, B.D.; Amendt, P.A.; Baker, K.L.; Casey, D.T.; Clark, D.S.; Döppner, T.; Eckart, M.J.; Field, J.E.; Gatu Johnson, Maria; Grim, G.P.; Hatarik, R.; Jeet, J.; Kerr, S.M.; Kilkenny, J.; Kritcher, A.L.; Meaney, K.D.; Milovich, J.L.; Munro, D.H.; Nora, R.C.; Pak, A.E.; Ralph, J.E.; Robey, H.F.; Ross, J.S.; Schlossberg, D.J.; Sepke, S.M.; Spears, B.K.; Young, C.V.; Zylstra, A.B. At the National Ignition Facility, inertial confinement fusion experiments aim to burn and ignite a hydrogen plasma to generate a net source of energy through the fusion of deuterium and tritium ions. The energy deposited by α-particles released from the deuterium–tritium fusion reaction plays the central role in heating the fuel to achieve a sustained thermonuclear burn. In the hydrodynamic picture, α-heating increases the temperature of the plasma, leading to increased reactivity because the mean ion kinetic energy increases. Therefore, the ion temperature is related to the mean ion kinetic energy. Here we use the moments of the neutron spectrum to study the relationship between the ion temperature (measured by the variance in the neutron kinetic energy spectrum) and the ion mean kinetic energy (measured by the shift in the mean neutron energy). We observe a departure from the relationship expected for plasmas where the ion relative kinetic energy distribution is Maxwell–Boltzmann, when the plasma begins to burn. Understanding the cause of this departure from hydrodynamic behaviour could be important for achieving robust and reproducible ignition. Submitted for publication in Nature Physics

Burning plasma achieved in inertial fusion

2025-04-07T08:47:55Z

Burning plasma achieved in inertial fusion Zylstra, A.B.; Hurricane, O.A.; Callahan, D.A.; Kritcher, A.L.; Ralph, J.; Robey, H.F.; Ross, J.S.; Young, C.; Baker, K.; Casey, D.; Döppner, T.; Divol, L.; Hohenberger; Le Pape, S.; Pak, A.; Patel, P.; Tommasini, R.; Ali, S.; Bachmann, B.; Benedetti, R.; Berger, D.; Betti, R.; Bhandarker, S.; Bionta, R.; Birge, N.; Bond, E.; Bradley, D.; Braun, T.; Briggs, T.; Bruhn, M.; Gatu Johnson, Maria; Jones, O.; Kerr, S.; Khan, S.; Kilkenny, J.; Kim, Y.; Geppert Kleinrath, H.; Geppert Kleinrath, V.; Kline, J.; Kroll, J.; Kong, C.; Landen, O.L.; Larson, D.; Lemos, N.C.; Lindl, J.; Mackinnon, A.; MacGowan, B.; Maclaren, S.; MacPhee, A.; Mariscal, D.; Marley, E.; Masse, L.; Meaney, K.; Meezan, N.; Michel, P.; Millot, M.; Milovich, J.; Moody, J.; Moore, A.; Newman, K.; Nikroo, A.; Nora, R.; Pelz, L.; Peterson, L.; Rice, N.; Rinderknecht, H.; Rosen, M.; Rubery, M.; Salmonson, J.; Sater, J.; Schlossberg, D.; Schneider, M.; Sequoia, K.; Shin, S.; Smalyuk, V.; Spears, B.; Springer, P.; Stadermann, M.; Stoupin, S.; Strozzi, D.; Thomas C.; Tubman, E.; Town, R.; Weber, C.; Widmann, K.; Wild, C.; Wilde, C.; Woods, T.; Woodworth, B.; Van Wonterghem, B.; Volegov, P.; Yang, S. The achievement of obtaining a burning plasma is a critical step toward self-sustaining fusion energy. A burning plasma is a fusion plasma where the alpha-particles created by the deuterium-tritium (DT) fusion reactions are the primary source of heating in the plasma, which is necessary to sustain and propagate the fusion reaction to enable high energy gain. After decades of fusion research, a burning plasma state has finally been achieved. Herein, we report upon the first burning-plasma experiments; this state was achieved using a strategy to increase the capsule spatial scale via two different implosion concepts, on the US National Ignition Facility. These experiments show energies from self-heating in excess of the mechanical work injected into the implosions satisfying several burning plasma metrics, the last experiment additionally shows that the fusion self-heating is greater than losses from radiation and heat conduction. These experiments triple the fusion yield performance and show significantly higher yield amplification from self-heating than prior results; remaining degradations can be reduced for even higher fusion performance. Submitted for publication in Nature - International Weekly Journal of Science

Intermediate energy proton irradiation: rapid, high-fidelity materials testing for fusion and fission energy systems

2025-04-07T09:23:19Z

Intermediate energy proton irradiation: rapid, high-fidelity materials testing for fusion and fission energy systems Jepeal, Steven J.; Snead, Lance; Hartwig, Zachary S. Fusion and advanced fission power plants require advanced nuclear materials to function under new, extreme environments. Understanding the evolution of mechanical and functional properties during radiation damage is essential to the design and commercial deployment of these systems. The shortcomings of existing methods could be addressed by a new technique - intermediate energy proton irradiation (IEPI) - using beams of 10 - 30 MeV protons to rapidly and uniformly damage bulk material specimens before direct testing of engineering properties. IEPI is shown to achieve high fidelity to fusion and fission environments in both primary damage production and transmutation, often superior to nuclear reactor or typical (low-range) ion irradiation. Modeling demonstrates that high dose rates (0.1 - 1 DPA/per day) can be achieved in bulk material specimens (100 - 300 microns) with low temperature gradients and induced radioactivity. The capabilities of IEPI are demonstrated through a 12 MeV proton irradiation and tensile test of 250 micron thick tensile specimens of a nickel alloy (Inconel 718), reproducing neutron-induced data. These results demonstrate that IEPI enables high throughput assessment of materials under reactor-relevant conditions, positioning IEPI to accelerate the pace of engineering-scale radiation damage testing and allow for quicker and more effective design of nuclear energy systems. Submitted for publication in Materials and Design

Poloidal impurity asymmetries, flow and transport in conventional neoclassical pedestals in the plateau and banana regimes

2025-04-07T09:20:33Z

Poloidal impurity asymmetries, flow and transport in conventional neoclassical pedestals in the plateau and banana regimes Bielajew, Rachel; Catto, Peter J. Charge exchange recombination spectroscopy (CXRS) allows the poloidal variation of the impurity density, temperature, and flow and the poloidal variation to be measured in the pedestal when determining the poloidally varying radial electric field. At present, impurity neoclassical pedestal models avoid the complications of treating finite poloidal gyroradius effects by assuming the impurity charge number is large compared to the main ion charge number. These models are extended slightly by retaining the simplest limit of the impurity radial pressure gradient to demonstrate that no substantial effect occurs due to impurity diamagnetic effects. More importantly, the neoclassical model is significantly extended to obtain a more comprehensive treatment of the main ions in the plateau and banana regimes. A parallel impurity momentum equation is derived that is consistent with previous results in the banana regime and reduces to the proper large aspect ratio form required in the plateau regime. The implications for interpreting the CXRS measurements are discussed by writing all results in terms of the gradient drive and poloidal flow. Submitted for publication in Journal of Plasma Physics

Merging of the superbanana plateau and /squareroot/nu transport regimes in nearly quasisymmetric stellarators

2026-02-05T04:54:16Z

Merging of the superbanana plateau and /squareroot/nu transport regimes in nearly quasisymmetric stellarators Catto, Peter J.; Tolman, Elizabeth Ann; Parra Diaz, Felix Ignacio Alpha particle confinement is one of the most demanding issues for stellarators. It now seems clear that it is possible to design optimized stellarators that confine the background plasma at near tokamak radial transport levels. Moreover, adequate collisionless alpha particle confinement is possible in the core of a highly optimized stellarator. Here, the collisional confinement of barely trapped alphas in an optimized stellarator is considered by accounting for the resonance due to the reversal in direction of the drift within a flux surface and investigating the sensitive role of magnetic shear in keeping this resonance close to the passing boundary in some nearly quasisymmetric stellarator configurations. The treatment relies on a narrow collisional boundary layer formulation that combines the responses of both these resonant pitch angle alphas and the remaining barely trapped alphas. A novel merged regime treatment leads to explicit expressions for the energy diffusivity for both superbanana plateau (or resonant plateau) and √ ν transport in the large aspect ratio limit for a slowing down tail alpha distribution function, where ν is the effective pitch angle scattering collision frequency of the trapped alphas off the background ions. Depending on the details of the optimization scheme and the sign of the magnetic shear, modest magnetic shear can be used to reduce superbanana (or resonant) plateau transport to below the √ ν transport level. In addition, a quasilinear equation retaining spatial diffusion is derived for a general alpha distribution function that allows the radial alpha transport to modify the distribution so it is no longer isotropic in velocity space. Submitted for publication in Journal of Plasma Physics

Predictions of core plasma performance for the SPARC tokamak

2025-04-07T08:24:41Z

Predictions of core plasma performance for the SPARC tokamak Rodriguez Fernandez, Pablo; Howard, Nathan T.; Greenwald, M.J.; Creely, A.J.; Hughes, Jerry W.; Wright, John C.; Holland, C.; Lin,Y.; Sciortino, Francesco; SPARC Team SPARC is designed to be a high-field, medium-size tokamak aimed at achieving net energy gain with Ion Cyclotron Range-of-Frequencies (ICRF) as its primary auxiliary heating mechanism. Empirical predictions with conservative physics indicate that SPARC baseline plasmas would reach Q~11, well above its mission objective of Q>2. To build confidence that SPARC will be successful, physics-based integrated modeling has also been performed. The TRANSP code coupled with the theory-based TGLF turbulence model and EPED predictions for pedestal stability find that Q~9 is attainable in standard H-mode operation and confirms Q>2 operation is feasible even with adverse assumptions. In this analysis, ion cyclotron waves are simulated with the full wave TORIC code and alpha heating is modeled with the Monte-Carlo fast ion NUBEAM module. Detailed analysis of expected turbulence regimes with linear and nonlinear CGYRO simulations is also presented, demonstrating that profile predictions with the TGLF reduced model are in reasonable agreement. Submitted for publication in Journal of Plasma Physics

Statistical description of coalescing magnetic islands via magnetic reconnection

2025-04-08T04:35:30Z

Statistical description of coalescing magnetic islands via magnetic reconnection Zhou, Muni; Wu, David H.; Loureiro, Nuno F.; Uzdensky, Dmitri A. The physical picture of interacting magnetic islands provides a useful paradigm for certain plasma dynamics in a variety of physical environments, such as the solar corona, the heliosheath and the Earth’s magnetosphere. In this work, we derive an island kinetic equation to describe the evolution of the island distribution function (in area and in flux of islands) subject to a collisional integral designed to account for the role of magnetic reconnection during island mergers. This equation is used to study the inverse transfer of magnetic energy through the coalescence of magnetic islands in two dimensions. We solve our island kinetic equation numerically for three different types of initial distribution: Dirac delta, Gaussian and power-law distributions. The time evolution of several key quantities is found to agree well with our analytical predictions: magnetic energy decays as t ̃−1, the number of islands decreases as t ̃−1 and the averaged area of islands grows as t ̃, where t ̃ is the time normalised to the characteristic reconnection time scale of islands. General properties of the distribution function and the magnetic energy spectrum are also studied. Finally, we discuss the underlying connection of our island-merger models to the (self-similar) decay of magnetohydrodynamic turbulence. Submitted for publication in Journal of Plasma Physics

Scaling of L-mode heat flux for ITER and COMPASS-U divertors, based on five tokamaks

2025-04-08T04:27:52Z

Scaling of L-mode heat flux for ITER and COMPASS-U divertors, based on five tokamaks Horacek, J.; Adamek, J.; Komm, M.; Seidl, J.; Vondracek, P.; Jardin, A.; Guillemaut, Ch.; Elmore, S.; Thornton; Jirakova, K.; Jaulmes, F.; Deng, G.; Gao, X.; Wang, L.; Ding, R.; Brunner, D.; LaBombard, Brian; Olsen, J.; Rasmussen, J.J.; Nielsen, A.H.; Naulin, V.; Ezzat, M.; Comacho, K.M.; Hron, M.; Matthews, G.F.; EUROfusionMSTI Team; JET Contributors; MAST-U Team This contribution aims to improve existing scalings of the L-mode power decay length Lambda_q_OMP, especially for plasma configurations with strike points at the ITER-relevant location—closed vertical divertor targets. We propose 13 new Lambda_q_OMP scalings based on data from the tokamaks JET, EAST, MAST, Alcator C-mod and COMPASS, and validate them against the output of the 2D turbulence code HESEL. The analysis covers 500 divertor heat flux profiles (obtained by probes or IR cameras), measured in L-mode discharges with varying 12 global plasma parameters (all well predictable). We find that the two previously published scalings (Eich 2013 J. Nucl. Mat. 438 S72) and (Scarabosio 2013 J. Nucl. Mat. 438 S426), which were based on outer target data from AUG and JET, describe the JET, C-mod and COMPASS profiles well. This holds not only at the outer horizontal and vertical targets, but surprisingly also at the inner vertical targets. In contrast, EAST, HESEL and especially MAST data are poorly described by these two scalings. We therefore derive 13 new scalings, which account for 85–92 % of the measured Lambda_q_OMP variability across all five tokamaks. Although each of the scalings is based on a different parameter combination, their predictions for the ITER and COMPASS-Upgrade tokamaks are very similar. Just before the L-H transition in the ITER baseline scenario, the presented scalings predict values Lambda_q_OMP = 3.0 +/-0.5 mm. For the COMPASS-Upgrade tokamak, all the scalings predict Lambda_q_OMP = 2.1 +/- 0.5 mm with a single exception of the scaling based on the stored plasma energy which predicts only 1.2 mm for both tokamaks. We encourage the reader to use as many of these scalings as possible, depending on available data. In attached plasma and using significant assumptions, our results imply steady-state surface-perpendicular heat flux around 10 MW/m^2 for ITER, and 20 MW/m^2 for COMPASS-Upgrade. Submitted for publication in Nuclear Fusion

Review of progress and challenges of key mechanical issues in high-field superconducting magnets

2025-04-07T08:53:53Z

Review of progress and challenges of key mechanical issues in high-field superconducting magnets Zhou, You-He; Park, Dongkeun; Iwasa, Yukikazu The development of modern science and technology requires high magnetic fields exceeding 25T. Second-generation high-temperature superconducting wires, i.e. REBCO (REBa2Cu3O7-x, RE refers to Y, Gd, Dy, Eu and other rare-earth elements) coated conductors (CCs), have become the first choice for high-field magnet construction because of their high irreversible magnetic field. The mechanical stresses caused by manufacturing, thermal mismatch and Lorenz forces closely influence electromagnetic performance during operation for REBCO CCs. In addition, the recently studied screen currents have effects on the mechanical characteristics of high-field REBCO magnets. In this review, the experimental and main theoretical works on critical current degradation, delamination and fatigue, and shear investigations on REBCO CCs, are reviewed at first. Then, research progress on the screening-current effect in the development of high-field superconducting magnets is introduced. Finally, the key mechanical problems facing the future development of high-field magnets based on REBCO CCs are prospected. Submitted for publication in National Science Review

The structure of 3-D collisional magnetized bow shocks in pulsed-power-driven plasma flows

2025-04-08T04:17:57Z

The structure of 3-D collisional magnetized bow shocks in pulsed-power-driven plasma flows Datta, R.; Russell, D.R.; Tang, I.; Clayson, T.; Suttle, L.G.; Chittenden, J.P.; Lebedev, S.V.; Hare, Jack D. We investigate 3D bow shocks in a highly collisional magnetized aluminum plasma, generated during the ablation phase of an exploding wire array on the MAGPIE facility (1.4 MA, 240 ns). Ablation of plasma from the wire array generates radially diverging, supersonic (MS ∼ 7), super- Alfvénic (MA > 1) magnetized flows with frozen-in magnetic flux (RM ≫1). These flows collide with an inductive probe placed in the flow, which serves both as the obstacle that generates the magnetized bow shock, and as a diagnostic of the advected magnetic field. Laser interferometry along two orthogonal lines of sight is used to measure the line-integrated electron density. A detached bow shock forms ahead of the probe, with a larger opening angle in the plane parallel to the magnetic field than in the plane normal to it. Since the resistive diffusion length of the plasma is comparable to the probe size, the magnetic field decouples from the ion fluid at the shock front and generates a hydrodynamic shock, whose structure is determined by the sonic Mach number, rather than the magnetosonic Mach number of the flow. 3D simulations performed using the resistive magnetohydrodynamic (MHD) code GORGON confirm this picture, but under-predict the anisotropy observed in the shape of the experimental bow shock, suggesting that non-MHD mechanisms may be important for modifying the shock structure. Submitted for publication in Journal of Plasma Physics

Data augmentation for disruption prediction via robust surrogate models

2025-04-07T09:06:18Z

Data augmentation for disruption prediction via robust surrogate models Rath, Katharina; Rügamer, David; Bischl, Bernd; von Toussaint, Udo; Rea, Cristina; Maris, Andrew D.; Granetz, Robert; Albert, Christopher G. The goal of this work is to generate large statistically representative datasets to train machine learning models for disruption prediction provided by data from few existing discharges. Such a comprehensive training database is important to achieve satisfying and reliable prediction results in artificial neural network classifiers. Here, we aim for a robust augmentation of the training database for multivariate time series data using Student-t process regression. We apply Student-t process regression in a state space formulation via Bayesian filtering to tackle challenges imposed by outliers and noise in the training data set and to reduce the computational complexity. Thus, the method can also be used if the time resolution is high. We use an uncorrelated model for each dimension and impose correlations afterwards via coloring transformations. We demonstrate the efficacy of our approach on plasma diagnostics data of three different disruption classes from the DIII-D tokamak. To evaluate if the distribution of the generated data is similar to the training data, we additionally perform statistical analyses using methods from time series analysis, descriptive statistics, and classic machine learning clustering algorithms. Submitted for publication in Journal of Plasma Physics

Towards Fast and Accurate Predictions of Radio Frequency Power Deposition and Current Profile via Data-driven Modeling

2025-04-08T04:18:22Z

Towards Fast and Accurate Predictions of Radio Frequency Power Deposition and Current Profile via Data-driven Modeling Wallace, Greg M.; Bai, Z.; Sadre, R.; Perciano, T.; Bertelli, N.; Shiraiwa, S.; Bethel, E.W.; Wright, John C. Three machine learning techniques (multilayer perceptron, random forest, and Gaussian process) provide fast surrogate models for lower hybrid current drive (LHCD) simulations. A single GENRAY/CQL3D simulation without radial diffusion of fast elec- trons requires several minutes of wall-clock time to complete, which is acceptable for many purposes, but too slow for integrated modeling and real-time control applications. The machine learning models use a database of 16,000+ GENRAY/CQL3D simulations for training, validation, and testing. Latin hypercube sampling methods ensure that the database covers the range of 9 input parameters (ne0, Te0, Ip, Bt, R0, n||, Zeff , Vloop, PLHCD) with sufficient density in all regions of parameter space. The surrogate models reduce the inference time from minutes to ∼ms with high accuracy across the input parameter space. Submitted for publication in Journal of Plasma Physics

Interaction of radio frequency waves with cylindrical density filaments -- scattering and radiation pressure

2025-04-08T04:12:17Z

Interaction of radio frequency waves with cylindrical density filaments -- scattering and radiation pressure Valvis, Spyridon I.; Ram, Abhay K.; Hizanidi, Kyriakos The propagation of radio frequency (RF) waves in tokamaks can be affected by filamentary structures, or blobs, that are present in the edge plasma and the scrape-off layer. The difference in the permittivity between the surrounding plasma and interior of a filament leads to reflection, refraction, and diffraction of the waves. This, in turn, can affect the power flow into the core of the plasma and reduce the efficiency of heating and/or current generation. The scattering of RF waves -- lower hybrid, helicon, and ion cyclotron waves -- by a single cylindrical filament, embedded in a background plasma, is studied using a full-wave analytical theory developed previously [A. K. Ram and K. Hizanidis, Phys. Plasmas \textbf{23}, 022504-1--022504-17 (2016)]. The theory assumes that the plasma in and around a filament is homogeneous and cold. A detailed scattering analysis reveals a variety of common features that exist among the three distinctly different RF waves. These common attributes can be inferred intuitively based on an examination of the cold plasma dispersion relation. The physical intuition is a useful step to understanding experimental observations on scattering, as well as results from simulations that include general forms of edge plasma turbulence. While a filament can affect the propagation of RF waves, the radiation force exerted by the waves can influence the filament. The force on a filament is determined using the Maxwell stress tensor. In 1905, Poynting was the first to evaluate and measure the radiation force on an interface separating two different dielectric media [J. H. Poynting, Phil. Mag. \textbf{9}, 393-406 (1905)]. For ordinary light propagating in vacuum and incident on a glass surface, Poynting noted that the surface is ``pulled'' towards the vacuum. In a magnetized cold plasma, there are two independent wave modes. Even if only one of these modes is excited by an RF antenna, a filament will couple power to the other mode -- a consequence of electromagnetic boundary conditions. This facet of scattering results in the radiation force having more diversified attributes than those in Poynting's seminal contribution. The direction of the force depends on the polarization of the incident wave and on the mode structure of the waves inside and in the vicinity of a filament. It can either pull the filament toward the RF source or push it away. For slow lower hybrid waves, filaments are pulled in regardless of whether they are more or less dense compared to the ambient plasma. For fast helicon and ion cyclotron waves, the direction of the force depends on the plasma and wave parameters; in particular, on the ambient density. For all three waves, the radiation force is large enough to impact the motion of a filament and could be measured experimentally. This suggests a possibility of modifying the edge turbulence using RF waves. Submitted for publication in Journal of Plasma Physics

Lower hybrid current drive in a tokamak for correlated passes through resonance

2025-04-07T08:52:06Z

Lower hybrid current drive in a tokamak for correlated passes through resonance Catto, Peter J. Standard quasilinear descriptions are based on the constant magnetic field form of the quasilinear operator so improperly treat the trapped electron modifications associated with tokamak geometry. Moreover, successive poloidal transits of the Landau resonance during lower hybrid current drive in a tokamak are well correlated, and these geometrical details must be properly retained to account for the presence of trapped electrons that do not contribute to the driven current. The recently derived quasilinear operator in tokamak geometry accounts for these features and finds that the quasilinear diffusivity is proportional to a delta function with a transit or bounce averaged argument (rather than a local Landau resonance condition). The new quasilinear operator is combined with the Cordey (Nucl. Fusion, vol. 16, 1976, pp. 499–507) eigenfunctions to properly derive a rather simple and compact analytic expression for the trapped electron modifications to the driven lower hybrid current and the efficiency of the current drive. Submitted for publication in Journal of Plasma Physics

Bootstrap current and parallel ion velocity in imperfectly optimized stellarators

2025-04-07T09:16:52Z

Bootstrap current and parallel ion velocity in imperfectly optimized stellarators Catto, Peter J.; Helander, Per A novel derivation of the parallel ion velocity, and the bootstrap and Pfirsch-Schlüter currents in an imperfectly optimized (that is, almost omnigenous) stellarator magnetic field, \vec B, is presented. It is shown that, when the conventional radially local form of the drift kinetic equation is employed, the flow velocity and the bootstrap current acquire a spurious contribution proportional to ω /ν , where ω denotes the \vec E × \vec B rotation frequency (due to the radial electric field E ) and ν the collision frequency. This contribution is particularly large in the squareroot ν regime and at smaller collisionalities, where ω /ν > 1 , and is presumably present in most numerical calculations, but it disappears if a more accurate drift kinetic equation is used. Submitted for publication in Journal of Plasma Physics

The Very High n Rydberg Series of Ar^16+ in Alcator C-Mod Tokamak Plasmas

2025-04-08T04:22:42Z

The Very High n Rydberg Series of Ar^16+ in Alcator C-Mod Tokamak Plasmas Rice, John E.; Sciortino, Francesco; Gu, M.; Cao, N.; Hughes, Jerry W.; Irby, J.H.; Marmar, E.S.; Mordijck, S.; Reinke, M.L.; Reksoatmodjo, R. X-ray transitions of the very high-n Rydberg series in Ar^16+ have been observed from Alcator C-Mod tokamak plasmas. Individual emission lines up to 1s16p - 1s^2 have been resolved and the central chord line brightnesses with principal quantum number n between 7 and 16 are generally found to decay as 1/n^alpha, with alpha slightly larger than 3. In the plasma periphery, emission from 1s9p - 1s^2 and 1s10p - 1s^2 are found to be significantly enhanced relative to this decrease, indicative of selected population of these levels through charge exchange between background neutral deuterium in the ground state and Ar^17+. An unresolved feature between the wavelengths of 1s27p - 1s^2 and 1s30p - 1s^2 is also present, which arises through charge exchange with neutral deuterium in the n^* = 3 excited state. The brightnesses of transitions populated by charge exchange are spatially up/down asymmetric, with an excess on the side of the magnetic surface X-point. The relative brightness of the unresolved very high-n feature compared to 1s7p - 1s^2 is found to increase with electron temperature and decrease with electron density. Simulations of line emission just on the long wavelength side of the Ar^16$ ionization limit indicate that the principal quantum number decay exponent is closer to alpha = 4 at very high n. The brightness dependence on n below 16 is in excellent agreement with calculations from the Flexible Atomic Code package. Submitted for publication in Journal of Physics B: Atomic, Molecular and Optical Physics

X-ray Observations of Ne-like Xe and Satellites from C-Mod Tokamak Plasmas

2025-04-07T09:20:23Z

X-ray Observations of Ne-like Xe and Satellites from C-Mod Tokamak Plasmas Rice, John E.; Fournier, K.B.; Kemp, G.E.; Bitter, M.; Cao, N.; Delgado-Aparicio, L.; Hill, K.; Hubbard, Amanda E.; Hughes, Jerry W.; Reinke, M.L. X-ray spectra in the wavelength range from 2.70 to 2.76 A from xenon (Z = 54) in near neon-like charge states have been observed in Alcator C-Mod tokamak plasmas. The 3D (2p^6 - (2p^5)_{3/2}3d_{5/2}, 2720.4 mA) and 3F (2p^6 - (2p^5)_{1/2}3s_{1/2}, 2729.0 mA) transitions from neon-like Xe^{44+} have been identified, along with nearby Na-, Mg- and Al-like satellites. The intensity ratio of 3D to the Mg-like satellite near 2.74 A increases strongly with electron temperature in the range from 3 to 4 keV. Submitted for publication in Journal of Physics B: Atomic, Molecular and Optical Physics

Helicon and lower hybrid current drive comparisons in tokamak geometry

2025-04-07T09:06:46Z

Helicon and lower hybrid current drive comparisons in tokamak geometry Catto, Peter J.; Zhou, Muni The parallel current driven by applied helicon waves is evaluated in tokamak geometry along with the radio frequency (rf) power absorbed by the passing electrons. The results are compared to the corresponding expressions for lower hybrid current drive. The efficiency of both current drive schemes is found to be the same in the single wave frequency, single mode number limit. The evaluation of the parallel currents is performed using an adjoint technique and tokamak geometry is retained by using an eigenfunction expansion appropriate for a transit averaged long mean free path treatment of electrons making correlated poloidal passes through the applied rf fields. Submitted for publication in Journal of Plasma Physics

Scattering of radio frequency waves by randomly modulated density interfaces in the edge of fusion plasmas

2025-04-07T09:01:53Z

Scattering of radio frequency waves by randomly modulated density interfaces in the edge of fusion plasmas Papadopoulos, A.D.; Glytus, E.N.; Ram, Abhay K.; Hizanidi, K. In the scrape-off layer and the edge region of a tokamak, the plasma is strongly turbulent and scatters the radio frequency (RF) electromagnetic waves that propagate through this region. It is important to know, whether used for diagnostics or for heating and current drive, the spectral properties of these scattered RF waves. The spectral changes influences the interpretation of the diagnostic-data obtained and the current and heating profi les. A full-wave, 3D electromagnetic code ScaRF (see Papadopoulos et al. 2019) has been developed for studying the RF wave propagation through turbulent plasma. ScaRF is a finite-difference frequency-domain (FDFD) method for solving Maxwell's equations. The magnetized plasma is de fined through the cold plasma, anisotropic permittivity tensor. As a result, ScaRF can be used to study the scattering of any cold plasma RF wave. It can be for the study of scattering of electron cyclotron waves in ITER-type and medium-sized tokamaks such as TCV, ASDEX-U, DIII-D. For the case of medium-sized tokamaks, there's experimental evidence that drift waves and rippling modes are present in the edge region (see Ritz et al. 1984). Hence, we study the scattering of RF waves by periodic density interfaces (plasma gratings) in the form of a superposition of spatial modes with varying periodicity and random amplitudes (see Papadopoulos et al. 2019). The power reflection coefficient (a random variable) is calculated for different realizations of the density interface. In this work, the uncertainty of the power reflection coefficient is rigorously quanti fied by use of the Polynomial Chaos Expansion (see Xiu & Karniadakis 2002) method in conjunction with the Smolyak sparse grid integration (see Papadopoulos et al. 2018) (PCE-SG). The PCE-SG method is proven accurate and much more efficient (roughly 2-orders of magnitude shorter execution time) compared to alternative methods such as the Monte Carlo (MC) approach. Submitted for publication in Journal of Plasma Physics

Multisatellite MMS Analysis of Electron Holes in the Earth's Magnetotail: Origin, Properties, Velocity Gap, and Transverse Instability

2025-04-07T08:27:11Z

Multisatellite MMS Analysis of Electron Holes in the Earth's Magnetotail: Origin, Properties, Velocity Gap, and Transverse Instability Lotekar, A.; Vasko, I.Y.; Mozer, F.S.; Hutchinson, Ian H.; Artemyev, A.V.; Bale, S.D.; Bonnell, J.W.; Ergun, R.; Giles, B.; Khotyaintsev, Yu. V.; Lindqvist, P.-A.; Russell, C.T.; Strangeway, R. We present a statistical analysis of more than 2400 bipolar electrostatic solitary waves measured aboard at least three MMS spacecraft in the Earth's magnetotail. These bipolar solitary waves are interpreted in terms of electron holes, because of positive electrostatic potentials. The multi- spacecraft interferometry is used to estimate the velocity of propagation of the electron holes and address their origin and properties. The electron hole velocities in the plasma rest frame are in the range from just a few km/s, that is much smaller than ion thermal velocity VTi, up to 20,000 km/s, which is comparable to electron thermal velocity VTe. We argue that fast electron holes with velocities larger than about 0.1 VTe are produced by bump-on-tail instabilities, while the most of slow electron holes with velocities below about 0.05 VTe is predominantly produced by warm bi- stream instabilities. We have identified a gap in the distribution of electron hole velocities between about VTi and 2VTi, which is considered to be an evidence for recently simulated self-acceleration process [Zhou and Hutchinson, 2018] or / and ion Landau damping of electron holes. In accordance with previous measurements, the amplitudes and parallel spatial scales of the electron holes are typically D d| | 10 D and 10-3 Te e0 0.1 Te. We show that electron hole amplitudes are below a threshold of the transverse electron hole instability and highly likely restricted by the nonlinear saturation criterion of electron streaming instabilities seeding electron hole formation. The transverse instability and nonlinear saturation criterion are suggested to restrict electron hole amplitudes as e0 me 2d2| |, where = min(, 1.5 ce), where is the increment of instabilities seeding electron hole formation, while ce is electron cyclotron frequency. Submitted for publication in Journal of Geophysical Research: Space Physics

Acoustic MEMS Sensor Array for Quench Detection of CICC Superconducting Cables

2025-04-07T09:12:08Z

Acoustic MEMS Sensor Array for Quench Detection of CICC Superconducting Cables Takayasu, Makoto A novel quench detection method using microelectro- mechanical system (MEMS) sensor technology has been investigated in use for high temperature superconducting (HTS) conductors such REBCO tape cables. The sensor array along a superconducting cable, such as a cable-in-conduit-conductor (CICC), is installed in a cooling channel. It will allow sensitive and quick detection for a local quench of a superconducting cable. This work has confirmed that a quench of a single REBCO tape can be detected in liquid nitrogen by a MEMS piezoelectric microphone sensor. The quench detection design utilizing a MEMS sensor array method is discussed for the case of a toroidal field (TF) magnets of a fusion Tokamak device. Submitted for publication in IEEE Transactions on Applied Superconductivity

Exploring MDSplus data-acquisition software and custom devices

2025-05-27T19:07:23Z

Exploring MDSplus data-acquisition software and custom devices Santoro, Fernando; Stillerman, Joshua; Lane Walsh, Stephen; Fredian, Thomas MDSplus is a software tool designed for data acquisition, storage, and analysis of complex scientific experiments. Over the years, MDSplus has primarily been used for data management for fusion experiments. This paper demonstrates that MDSplus can be used for a much wider variety of systems and experiments. We present a step-by-step tutorial describing how to create a simple experiment, manage the data, and analyze it using MDSplus and Python. To this end, a custom example device was developed to be used as the data source. This device was built on an opensource electronic hardware platform, and it consists of a microcontroller and two sensors. We read data from these sensors, store it in MDSplus, and use JupyterLab to visualize and process it. This project and code demo are available on the GitHub site at this URL: https://github.com/santorofer/MDSplusAndCustomeDevices Submitted for publication in Fusion Engineering and Design

ARC reactor materials: Activation analysis and optimization

2025-04-08T04:25:56Z

ARC reactor materials: Activation analysis and optimization Bocci, B.; Hartwig, Zachary S.; Segantin, S.; Testoni, R.; Whyte, D.; Zucchetti, M. Nowadays, Fusion Energy is one of the most important sources under study. During the last years, different designs of fusion reactors were considered. At the MIT, an innovative design was created: ARC, the Affordable Robust Compact reactor. It takes advantage of the innovative aspects of recent progress in fusion technology, such as high temperature superconductors, that permit to decrease the dimensions of the machine, reaching at the same time high magnetic fields. Our main goal is the low-activation analysis of possible structural materials for the vacuum vessel, which is designed as a single-piece placed between the first-wall and the tank that contains the breeding blanket. Due to its position, the vacuum vessel is subject to high neutron flux, which can activate it and cause the reduction of the component lifetime and decommissioning problems. The activation analysis was done also for the liquid breeder FLiBe, compared with Lithium-Lead. Codes used for the low-activation analysis were MCNP and FISPACT-II. The first one is based on a neutronics model and for each component a certain neutron flux is evaluated. For FISPACT-II, the main input is the composition of the analyzed material, the neutron flux and the irradiation time. Results from FISPACT-II are the time behavior of specific activity, contact dose rate. To assess suitable structural materials for the vacuum vessel, low-activation properties were considered. Vanadium alloys turn out to be one of the best alternatives to the present material, Inconel-718. Finally, isotopic tailoring and elemental substitution methods were applied. Here, the composition of each alloy is analyzed and critical isotopes or elements are eliminated or reduced. After the modifications, new simulations are done, and those leading to significant improvements in the final results are highlighted. Submitted for publication in Fusion Engineering and Design

W0.5TaTiVCr-based composite reinforced with W-mesh for Fusion Plasma-Facing Applications

2025-04-07T08:46:37Z

W0.5TaTiVCr-based composite reinforced with W-mesh for Fusion Plasma-Facing Applications Waseem, Owais Ahmed; Ryu, Ho Jin We present research into tungsten (W) alloy-based composites reinforced with W-mesh. Due to low activation and higher strength properties, W0.5TaTiVCr was used as a matrix material. Layers of W-mesh (Wmesh) were embedded in W0.5TaTiVCr for improving ductility and toughness. We employed elemental powder mixing and spark plasma sintering (SPS) at 1600 °C for sample preparation, which is a simpler method as compared to chemical vapor infiltration and hot isostatic pressing. The microstructural analysis shows W-mesh that is well-bonded with the W0.5TaTiVCr matrix, which exhibits multiple phases and BCC structure. The room temperature compressive fracture strain of W0.5TaTiVCr/Wmesh composites show an improvement from ~3.5% to ~15.8% due to increase in Wmesh concentration from 10 wt% to 50 wt%, whereas the compressive yield strength changes from ~1900 MPa to ~1700 MPa (at room temperature) and ~1200 MPa to ~950 MPa (at 1200 °C). The W0.5TaTiVCr matrix alone shows ~7.7 MPa·m1/2 fracture strain, and the addition of 10 wt%Wmesh in W0.5TaTiVCr results in more than a two-fold increase in fracture toughness (up to ~20 MPa·m1/2), which suggests a potential use of this material in fusion reactors. Submitted for publication in Functional Composites and Structures

Qubit Lattice Algorithm Simulations of Maxwell’s Equations for Scattering from Anisotropic Dielectric Objects

2025-04-08T04:27:47Z

Qubit Lattice Algorithm Simulations of Maxwell’s Equations for Scattering from Anisotropic Dielectric Objects Vahala, George; Soe, Min; Vahala, Linda; Ram, Abhay K.; Koukoutsis, Efstratios; Hizanidis, Kyriakos A Dyson map explicitly determines the appropriate basis of electromagnetic fields which yields a unitary representation of the Maxwell equations in an inhomogeneous medium. A qubit lattice algorithm (QLA) is then developed perturbatively to solve this representation of Maxwell equations. QLA consists of an interleaved unitary sequence of collision operators (that entangle on lattice-site qubits) and streaming operators (that move this entanglement throughout the lattice). External potential operators are introduced to handle gradients in the refractive indices, and these operators are typically non-unitary, but sparse matrices. By also interleaving the external potential operators with the unitary collide-stream operators one achieves a QLA which conserves energy to high accuracy. Some two dimensional simulations results are presented for the scattering of a one-dimensional (1D) pulse off a localized anisotropic dielectric object. Submitted for publication in Computers & Fluids

Magnetogenesis in a Collisionless Plasma: From Weibel Instability to Turbulent Dynamo

2025-04-07T08:50:15Z

Magnetogenesis in a Collisionless Plasma: From Weibel Instability to Turbulent Dynamo Zhou, Muni; Zhdankin, Vladimir; Kunz, Matthew W.; Loureiro, Nuno F.; Uzdensky, Dmitri A. We report on a first-principles numerical and theoretical study of plasma dynamo in a fully kinetic framework. By applying an external mechanical force to an initially unmagnetized plasma, we develop a self-consistent treatment of the generation of "seed" magnetic fields, the formation of turbulence, and the inductive amplification of fields by the fluctuation dynamo. Driven large-scale motions in an unmagnetized, weakly collisional plasma are subject to strong phase mixing, which leads to the development of thermal pressure anisotropy. This anisotropy triggers the Weibel instability, which produces filamentary "seed" magnetic fields on plasma-kinetic scales. The plasma is thereby magnetized, enabling efficient stretching and folding of the fields by the plasma motions and the development of Larmor-scale kinetic instabilities such as the firehose and mirror. The scattering of particles off the associated microscale magnetic fluctuations provides an effective viscosity, regulating the field morphology and turbulence. During this process, the seed field is further amplified by the fluctuation dynamo until energy equipartition with the turbulent flow is reached. By demonstrating that equipartition magnetic fields can be generated from an initially unmagnetized plasma through large-scale turbulent flows, this work has important implications for the origin and amplification of magnetic fields in the intracluster and intergalactic mediums. Submitted for publication in Astrophysical Journal

Coherent high-power RF wakefield generation by electron bunch trains in a metamaterial structure

2025-04-07T08:26:48Z

Coherent high-power RF wakefield generation by electron bunch trains in a metamaterial structure Lu, Xueying; Picard, Julian F.; Shapiro, Michael A.; Mastovsky, Ivan; Temkin, Richard J.; Conde, Manoel; Power, John G.; Shao, Jiahang; Wisniewski, Eric E.; Peng, Maowanghui; Seok, Jimin; Doran, Scott; Jing, Chunguang We present an experimental study of coherent high-power wakefield generation in a metamaterial (MTM) structure at 11.7 GHz by 65 MeV electron bunch trains at the Argonne Wakefield Accelerator (AWA), following a previous experiment, the Stage-I experiment, at AWA. Both the Stage-II experiment, reported in this paper, and the Stage- I experiment were conducted using MTM structures, which are all-metal periodic structures with the period much smaller than the wavelength. Differences between the two experiments include: (1) Structure length (Stage-I 8 cm, Stage-II 20 cm); (2) Number of bunches used to excite the structure (Stage-I with 2 bunches, up to 85 nC of total charge; Stage-II with 8 bunches, up to 224 nC of total charge); (3) Highest peak power measured (Stage-I 80 MW in a 2 ns pulse, Stage-II 380 MW in a 10 ns pulse). The high-power radiofrequency (RF) pulses were generated by reversed Cherenkov radiation of the electron beam due to the negative group velocity in the MTM structures. Because the radiation is coherent, a train of bunches with a proper spacing can build up to achieve a high peak power. The observed output power levels are very promising for future applications in direct collinear wakefield acceleration or in transfer to a second accelerator for two beam acceleration. Submitted for publication in Applied Physics Letters

Experiments to explore the influence of pulse shaping at the National Ignition Facility

2025-04-08T04:35:26Z

Experiments to explore the influence of pulse shaping at the National Ignition Facility Thomas, C.A.; Campbell, E.M.; Baker, K.L.; Casey, D.T.; Hohenberger, M.; Kritcher, A.L.; Spears, B.K.; Khan, S.F.; Nora, R.; Woods, D.T.; Milovich, J.L.; Berger, R.L.; Strozzi, D.; Ho, D.D.; Clark, D.; Bachmann, B.; Benedetti, L.R.; Bionta, R.; Celliers, P.M.; Fittinghoff, D.N.; Grim, G.; Hatarik, R.; Izumi, N.; Kyrala, G.; Ma, T.; Millot, M.; Nagel, S.R.; Patel, P.K.; Yeamans, C.; Nikroo, A.; Tabak, M.; Gatu Johnson, Maria; Volegov, P.L.; Finnegan, S.M. The shaping of the drive pulse in time is a key tool in the design of fusion experiments that use inertia to confine burning plasmas. It is directly related to the adiabat and compressibility of the DT fuel, and the characteristics of the laser and target that are needed to ignite. With this in mind, we have performed experiments at the National Ignition Facility that test small changes in the shape of the pulse. In contrast to theory, we find implosions at lower adiabats can have reduced yield and areal density. We discuss implications to performance and the mechanism(s) that could be responsible. Submitted for publication in Physics of Plasmas

Symmetry tuning and high energy coupling for an Al capsule in a Au rugby hohlraum on NIF

2025-04-07T08:39:43Z

Symmetry tuning and high energy coupling for an Al capsule in a Au rugby hohlraum on NIF Ping, Y.; Smalyuk, A.; Amendt, P.; Khan, S.; Tommasini, R.; Dewald, E.; Field, J.E.; Graziani, F.; Hartouni, E.; Johnson, S.; Landen, O.L.; Lindl, J.; MacPhee, A.; Nikroo, A.; Nora, R.; Prisbrey, S.; Ralph, J.; Seugling, R.; Strozzi, D.; Tipton, R.E.; Wang, Y.M.; Kim, Y.; Loomis, E.; Meaney, K.D.; Merritt, E.; Montgomery, D.; Kabadi, Neel V.; Lahmann, Brandon; Petrasso, Richard D. Experiments on imploding an Al capsule in a Au rugby hohlraum with up to 1.5 MJ laser drive were performed on the National Ignition Facility (NIF). The capsule diameter was 3.0 mm with ∼ 1 MJ drive and 3.4 mm with ∼ 1.5 MJ drive. Effective symmetry tuning by modifying the rugby hohlraum shape was demonstrated, and good shell symmetry was achieved for 3.4 mm capsules at a convergence of ∼10. The nuclear bang time and the shell velocity from simulations agree with experimental data, indicating ∼500 kJ coupling with 1.5 MJ drive, or ∼30% efficiency. The peak velocity reached above 300 km/s for a 120 µm-thick Al capsule. The laser backscatter inside the low-gas-fill rugby hohlraum was very low (<4%) at both scales. The high energy coupling allows implosion designs with increased adiabat which in turn increases the tolerance to detrimental effects of instabilities and asymmetries. These encouraging experimental results open new opportunities for both the mainline single-shell scheme and the double-shell design toward ignition. Submitted for publication in Physics of Plasmas

Evidence of non-Maxwellian ion velocity distributions in spherical shock-driven implosions

2025-04-08T04:40:19Z

Evidence of non-Maxwellian ion velocity distributions in spherical shock-driven implosions Mannion, O.; Taitano, W.T.; Appelbe, B.D.; Crilly, A.J.; Forrest, C.J.; Glebov, V. Yu.; Knauer, J.P.; McKenty, P.W.; Mohamed, Z.L.; Stoeckl, C.; Keenan, B.D.; Chittenden, J.P.; Adrian, Patrick J.; Frenje, Johan A.; Kabadi, Neel V.; Gatu Johnson, Maria; Regan, S.P. The ion velocity distribution functions of thermonuclear plasmas generated by spherical laser direct drive implosions are studied using deuterium-tritium (DT) and deuterium-deuterium (DD) fusion neutron energy spectrum measurements. A hydrodynamic Maxwellian plasma model accurately describes measurements made from lower temperature (< 10 keV), hydrodynamic like plasmas, but is insufficient to describe measurements made from higher temperature more kinetic like plasmas. The high temperature measurements are more consistent with Vlasov-Fokker-Planck (VFP) simulation results which predict the presence of a bimodal plasma ion velocity distribution near peak neutron production. These measurements provide direct experimental evidence of non-Maxwellian ion velocity distributions in spherical shock driven implosions and provide useful data for benchmarking kinetic VFP simulations. Submitted for publication in Physical Review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics

Diagnosing the Origin and Impact of Low-mode Asymmetries in Ignition Experiments at the National Ignition Facility

2025-04-07T08:43:58Z

Diagnosing the Origin and Impact of Low-mode Asymmetries in Ignition Experiments at the National Ignition Facility Casey, D.; MacGowan, B.; Hurricane, O.; Landen, O.; Nora, R.; Haan, S.; Kritcher, A.; Zylstra, A.; Ralph, J.; Dewald, E.; Hohenberger, M.; Pak, A.; Springer, P.; Weber, C.; Milovich, J.; Divol, L.; Hartouni, E.; Bionta, R.; Hahn, K.; Schlossberg, D.; Moore, A.; Gatu Johnson, Maria Inertial confinement fusion ignition requires high inflight shell velocity, good energy coupling between the hotspot and shell, and high areal-density at peak compression. Three-dimensional asymmetries caused by imperfections in the drive symmetry or target can grow and damage the coupling and confinement. Recent high-yield experiments have shown that low-mode asymmetries are a key degradation mechanism and contribute to variability. We show the experimental signatures and impacts of asymmetry change with increasing implosion yield given the same initial cause. This work has implications for improving robustness to a key degradation in ignition experiments. Submitted for publication in Physical Review E

Predictive modeling of NSTX discharges with the updated multi-mode anomalous transport module

2025-04-07T08:27:35Z

Predictive modeling of NSTX discharges with the updated multi-mode anomalous transport module Rafiq, Tariq; Wilson, Christopher; Clauser, Cesar F.; Schuster, Eugenio; Weiland, Jan; Anderson, Johan; Kaye, Stanley M.; Pankin, Alexei; LeBlanc, Benoit P.; Bell, Ronald E. The objective of this study is twofold: firstly, to demonstrate the consistency between the anomalous transport results produced by updated Multi-Mode Model (MMM) version 9.04 and those obtained through gyrokinetic simulations; and secondly, to showcase MMM's ability to predict electron and ion temperature profiles in low aspect ratio, high beta NSTX discharges. MMM encompasses a range of transport mechanisms driven by electron and ion temperature gradients, trapped electrons, kinetic ballooning, peeling, microtearing, and drift resistive inertial ballooning modes. These modes within MMM are being verified through corresponding gyrokinetic results. The modes that potentially contribute to ion thermal transport are stable in MMM, aligning with both experimental data and findings from linear CGYRO simulations. The isotope effects on these modes are also studied and higher mass is found to be stabilizing, consistent with the experimental trend. The electron thermal power across the flux surface is computed within MMM and compared to experimental measurements and nonlinear CGYRO simulation results. Specifically, the electron temperature gradient modes (ETGM) within MMM account for 2.0 MW of thermal power, consistent with experimental findings. It is noteworthy that the ETGM model requires approximately 5.0 ms of computation time on a standard desktop, while nonlinear CGYRO simulations necessitate 8.0 hours on 8 K cores. MMM proves to be highly computationally efficient, a crucial attribute for various applications, including real-time control, tokamak scenario optimization, and uncertainty quantification of experimental data. Submitted for publication in Nuclear Fusion

Predictions of improved confinement in SPARC via energetic particle turbulence stabilization

2025-04-08T04:12:05Z

Predictions of improved confinement in SPARC via energetic particle turbulence stabilization Di Siena, A.; Rodriguez Fernandez, Pablo; Howard, Nathan T.; Bañón Navarro, A.; Bilato, R.; Görler, T.; Poli, E.; Merlo, G.; Wright, John C.; Greenwald, M.; Jenko, F. The recent progress in high-temperature superconductor technologies has led to the design and construction of SPARC, a compact tokamak device expected to reach plasma breakeven with up to 25MW of external ion cyclotron resonant heating (ICRH) power. This manuscript presents local (flux-tube) and radially global gyrokinetic GENE (Jenko et al 2000 Phys. Plasmas 7 1904) simulations for a reduced-field and current H-mode SPARC scenario showing that supra-thermal particles - generated via ICRH - strongly suppress ion-scale turbulent transport by triggering a fast ion-induced anomalous transport barrier (F-ATB). The trigger mechanism is identified as a wave- particle resonant interaction between the fast particle population and plasma micro-instabilities (Di Siena et al 2021 Phys. Rev. Lett. 125 025002). By performing a series of global simulations employing different profiles for the thermal ions, we show that the fusion gain of this SPARC scenario could be substantially enhanced by up to ∼ 80% by exploiting this fast ion stabilizing mechanism. A study is also presented to further optimize the energetic particle profiles, thus possibly leading experimentally to an even more significant fusion gain. Submitted for publication in Nuclear Fusion

Experiments on excitation of Alfvén eigenmodes by alpha-particles with bump-on-tail distribution in JET DTE2 plasmas

2025-04-08T04:17:21Z

Experiments on excitation of Alfvén eigenmodes by alpha-particles with bump-on-tail distribution in JET DTE2 plasmas Sharapov, S.E.; Oliver, H.J.C.; Garcia, J.; Keeling, D.L.; Dreval, M.; Goloborod'ko, V.; Kazakov, Ye. O.; Kiptily, V.G.; Stancar, Z.; Bonofiglo, P.J.; Coelho, R.; Craciunescu, T.; Ferreira, J.; Figueiredo, A.; Fil, N.; Fitzgerald, M.; Nabais, F.; Nocente, M.; Puglia, P.G.; Rivero-Rodriguez, J.; Rodrigues, P.; Salewski, M.; Tinguely, R. Alex; Zakharov, L.E.; JET contributors Dedicated experiments were performed in JET DTE2 plasmas for obtaining an α-particle bump-on-tail (BOT) distribution aiming at exciting Alfvén Eigenmodes (AEs). NBI-only heating with modulated power was used so that fusion-born α-particles were the only ions present in the MeV energy range in these DT plasmas. The beam power modulation on a time scale shorter than the α-particle slowing down time was chosen for modulating the α-particle source and thus sustaining a BOT in the α-particle distribution. High-frequency modes in the TAE frequency range and multiple short-lived modes in a wider frequency range have been detected in these DT discharges with interferometry, soft X-ray cameras, and reflectometry. The modes observed were localised close to the magnetic axis, and were not seen in the Mirnov coils. Analysis with the TRANSP and Fokker-Planck FIDIT codes confirms that α-particle distributions with bump-on-tail in energy were achieved during some time intervals in these discharges though no clear correlation was found between the times of the high-frequency mode excitation and the BOT time intervals. The combined MHD and kinetic modelling studies show that the high-frequency mode in the TAE frequency range is best fitted with a TAE of toroidal mode number n= 9. This mode is driven mostly by the on-axis beam ions while the smaller drive due to the pressure gradient of α-particles allows overcoming the marginal stability and exciting the mode [H.J.C. Oliver et al. Toroidal Alfvén eigenmodes observed in low power JET deuterium-tritium plasmas, to be submitted to Nuclear Fusion (2023)]. The observed multiple short-lived modes in a wider frequency range are identified as the on-axis kinetic Alfvén eigenmodes predicted in [M.N. Rosenbluth, P.H. Rutherford, Phys. Rev. Lett. 34 (1975) 1428]. Submitted for publication in Nuclear Fusion

Inference of Main Ion Particle Transport Coefficients with Experimentally Constrained Neutral Ionization during Edge Localized Mode Recovery on DIII-D

2025-04-07T09:22:33Z

Inference of Main Ion Particle Transport Coefficients with Experimentally Constrained Neutral Ionization during Edge Localized Mode Recovery on DIII-D Rosenthal, Aaron M.; Hughes, Jerry W.; Laggner, Florian M.; Odstrcil, Tomas; Bortolon, Alessandro; Wilks, Theresa M.; Sciortino, Francesco The plasma and neutral density dynamics after an Edge Localized Mode (ELM) are investigated and utilized to infer the plasma transport coefficients for the density pedestal. The LLAMA diagnostic provides sub-millisecond profile measurements of the ionization and neutral density and shows significant poloidal asymmetries in both. Exploiting the absolute calibration of the LLAMA diagnostic allows quantitative comparison to the electron and main ion density profiles determined by charge-exchange recombination, Thomson scattering and interferometry. Separation of diffusion and convection contributions to the density pedestal transport are investigated through flux gradient methods and time-dependent forward modeling with Bayesian inference by adaptation of the Aurora transport code and IMPRAD framework to main ion particle transport. Both methods suggest time- dependent transport coefficients and are consistent with an inward particle pinch on the order of 1 m s^{−1} and diffusion coefficient of 0.05 m^2 s^{−1} in the steep density gradient region of the pedestal. While it is possible to recreate the experimentally observed phenomena with no pinch in the pedestal, low diffusion in the core and high outward convection in the near scrape-off layer are required without an inward pedestal pinch. Submitted for publication in Nuclear Fusion

Examination of stiff ion temperature gradient mode physics in simulations of DIII-D H-mode transport

2025-04-08T04:19:13Z

Examination of stiff ion temperature gradient mode physics in simulations of DIII-D H-mode transport Holland, C.; Luce, T.; Grierson, B.A.; Smith, S.P.; Marinoni, Alessandro; Burrell, K.H.; Petty, C.C.; Bass, E.M. A systematic evaluation of gyrokinetic and gyrofluid model predictions of ion temperature gradient (ITG) stability and transport using parameters from DIII-D high confinement mode (H-mode) plasmas has been performed. The nonlinear CGYRO code is used to make the gyrokinetic predictions, and the quasilinear TGLF model for the corresponding gyrofluid predictions. The assessments are made at three radii (normalized toroidal flux ρtor = 0.4, 0.55, and 0.7) in three different plasma scenarios with varying levels of neutral beam heating and torque. For each of the nine cases (3 radii × 3 scenarios) considered, ITG turbulence is found to be the dominant long-wavelength instability and transport mechanism. The inclusions of both transverse magnetic fluctuations and dynamic fast beam ions are stabilizing for all cases considered, with strongest effects seen at ρor = 0.4 where the fast ion population and normalized plasma pressure β = 2μ0nT/B2 are highest. The further inclusion of parallel magnetic fluctuations does not have a meaningful impact on the ITG turbulence in these scenarios, but does destabilize (in combination with fast ions) new high-frequency instabilities at ρtor = 0.4 in the high power scenarios. In each case the linear and nonlinear ITG critical gradients are predicted to be lower than the measured ITG scale lengths and their associated uncertainties. Inclusion of equilibrium flow shear in the transport predictions generally leads to an upshift in effective critical gradient rather than a qualitative change in the predicted stiffness, with stronger responses typically seen in the gyrokinetic predictions than in the gyrofluid results. However, in most cases these upshifted gradients still remain below the measured values and their uncertainties. Although the predicted critical gradients are below the measured gradients, both models predicted flux-matching gradients consistent with measured values in six of the nine cases considered, with no clear systematic over- or underprediction. Thus, while the experimental ion temperature profiles do not appear to be closely pinned to the ITG critical gradient, both gyrokinetic and gyrofluid models are able to accurately match the measured gradients reasonably well in most cases. Submitted for publication in Nuclear Fusion

Shattered pellet penetration in low and high energy plasmas on DIII-D

2025-04-07T08:34:31Z

Shattered pellet penetration in low and high energy plasmas on DIII-D Raman, R.; Sweeney, Ryan; Moyer, R.A.; Eidietis, N.W.; Shiraki, D.; Herfindal, J.L.; Sachdev, J.; Hollmann, E.M.; Jardin, S.C.; Baylor, L.R.; Wilcox, R.; Carlstrom, T.; Osborne, T.; Eldon, D.; Menard, J.E.; Luncford, R.; Grierson, B. Shattered pellet injection (SPI) has been adopted as the baseline disruption mitigation system for ITER, as the radiative payload penetration into DIII-D plasmas from SPI is superior to those using the massive gas injection (MGI) method. Because of the substantial differences in the energy content of ITER plasma and those in present experiments, reliable 3D MHD modeling, benchmarked against present experiments is needed to project to ITER plasmas. In support of these needs, the depth of SPI fragment penetration in DIII-D plasmas was investigated by injecting SPI into two discharges with vastly different energy content and pedestal height. 400 Torr-L pure Ne fragmented pellets at a velocity of about 200 m s−1 were injected into a 0.2 MJ L-mode discharge and a 2 MJ super H-mode discharge. Results show deep penetration of SPI fragments into low-energy plasmas in DIII-D. SPI fragment penetration is reduced as the plasma energy content increases, with some discharges exhibiting penetration that is confined to the outer regions of the plasma. The injected SPI fragments are also spread out over a distance of about 20 cm, which results in some fragments arriving near the end of or after the thermal quench is over. Submitted for publication in Nuclear Fusion

Deficiencies in compression and yield in x-ray-driven implosions

2025-04-07T08:56:11Z

Deficiencies in compression and yield in x-ray-driven implosions Thomas, C.A.; Campbell, E.M.; Baker, K.L.; Casey, D.T.; Hohenberger, M.; Kritcher, A.L.; Spears, B.K.; Khan, S.F.; Nora, R.; Woods, D.T.; Milovich, J.L.; Berger, R.L.; Strozzi, D.; Ho, D.D.; Clark, D.; Bachmann, B.; Benedetti, L.R.; Bionta, R.; Celliers, P.M.; Fittinghoff, D.N.; Grim, G.; Hatarik, R.; Izumi, N.; Kyrala, G.; Ma, T.; Millot, M.; Nagel, S.R.; Patel, P.K.; Yeamans, C.; Nikroo, A.; Tabak, M.; Gatu Johnson, Maria; Volegov, P.L.; Finnegan, S.M. This paper analyzes x-ray–driven implosions that are designed to be less sensitive to 2-D and 3-D effects in hohlraum and capsule physics. Key performance metrics including the burn-averaged ion temperature, hot-spot areal density, and fusion yield are found to agree with simulations where the design adiabat (internal pressure) is multiplied by a factor of 1.4. These results motivate the development of a simple model for interpreting experimental data, which is then used to quantify how improvements in compression could help achieve ignition. Submitted for publication in Physics of Plasmas

Oblate electron holes are not attributable to anisotropic shielding

2025-04-08T04:08:08Z

Oblate electron holes are not attributable to anisotropic shielding Hutchinson, Ian H. Shielding mechanisms' influence on the ratio of perpendicular to parallel scale lengths of multidimensional plasma electron hole equilibria are analyzed theoretically and computationally. It is shown that the ``gyrokinetic'' model, invoking perpendicular polarization, is based on a misunderstanding and cannot explain the observational trend that greater transverse extent accompanies lower magnetic field. Instead, the potential in the wings of the hole, outside the region of trapped-electron depletion, has isotropic shielding giving $\phi\propto {\rm e}^{-r/L}/r$, with the shielding length $L$ equal to the Debye length for holes much slower than the electron thermal speed. Particle in cell simulations confirm the analysis. Trapped electron charge distribution anisotropy must therefore instead underlie the oblate shape of electron holes. Submitted for publication in Physics of Plasmas

Alpha heating of indirect-drive layered implosions on the National Ignition Facility

2025-04-08T04:27:08Z

Alpha heating of indirect-drive layered implosions on the National Ignition Facility Baker, K.L.; MacLaren, S.; Jones, O.; Spears, B.K.; Patel, P.K.; Nora, R.; Divol, L.; Landen, O.L.; Anderson, G.J.; Gaffney, J.; Kruse, M.; Hurricane, O.A.; Callahan, D.A.; Christopherson, A.R.; Salmonson, J.; Hartouni, E.P.; Döppner, T.; Dewald, E.; Tommasini, R.; Thomas, C.A.; Weber, C.; Clark, D.; Casey, D.T.; Hohenberger, M.; Khan, S.; Woods, T.; Milovich, J.L.; Berger, R.L.; Strozzi, D.; Kritcher, A.; Bachmann, B.; Benedetti, R.; Bionta, R.; Celliers, P.M.; Fittinghoff, D.; Hatarik, R.; Izumi, N.; Gatu Johnson, Maria; Kyrala, G.; Ma, T.; Meaney, K.; Millot, M.; Nagel, S.R.; Pak, A.; Volegov, P.L.; Yeamans, C.; Wilde, C. In order to understand how close current layered implosions in indirect-drive inertial confinement fusion are to ignition, it is necessary to measure the level of alpha heating present. To this end, pairs of experiments were performed that consisted of a low-yield tritium–hydrogen–deuterium (THD) layered implosion and a highyield deuterium–tritium (DT) layered implosion to validate experimentally current simulation-based methods of determining yield amplification. The THD capsules were designed to reduce simultaneously DT neutron yield (alpha heating) and maintain hydrodynamic similarity with the higher yield DT capsules. The ratio of the yields measured in these experiments then allowed the alpha heating level of the DT layered implosions to be determined. The level of alpha heating inferred is consistent with fits to simulations expressed in terms of experimentally measurable quantities and enables us to infer the level of alpha heating in recent high-performing implosions. Submitted for publication in Physical Review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics

Uncovering turbulent plasma dynamics via deep learning from partial observations

2025-04-08T04:08:35Z

Uncovering turbulent plasma dynamics via deep learning from partial observations Mathews, Abhilash; Francisquez, M.; Hughes, Jerry W.; Hatch, D.R.; Zhu, B.; Rogers, B.N. One of the most intensely studied aspects of magnetic confinement fusion is edge plasma turbulence which is critical to reactor performance and operation. Drift-reduced Braginskii two-fluid theory has for decades been widely applied to model boundary plasmas with varying success. Towards better understanding edge turbulence in both theory and experiment, we demonstrate that a novel multi-network physics-informed deep learning framework constrained by partial differential equations can accurately learn turbulent fields consistent with the two-fluid theory from partial observations of electron pressure which is not otherwise possible using conventional equilibrium models. This technique presents a novel paradigm for the advanced design of plasma diagnostics and validation of magnetized plasma turbulence theories in challenging thermonuclear environments. Submitted for publication in Physical Review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics

Proof-of-Principle Experiment on the Dynamic Shell Formation for Inertial Confinement Fusion

2025-04-08T04:42:26Z

Proof-of-Principle Experiment on the Dynamic Shell Formation for Inertial Confinement Fusion Igumenshchev, I.V.; Theobald, W.; Stoeckl, C.; Shah, R.C.; Bishel, D.T.; Goncharov, V.N.; Bonino, M.J.; Campbell, E.M.; Ceurvorst, L.; Chin, D.A.; Collins, T.J.B.; Fess, S.; Harding, D.R.; Sampat, S.; Shaffer, N.R.; Shvydky, A.; Smith, E.A.; Trickey, W.T.; Waxer, L.J.; Colaïtis, A.; Liotard, R.; Adrian, Patrick J.; Atzeni, S.; Barbato, F.; Savino, L.; Alfonso, N.; Haid, A.; Do, Mi In the dynamic-shell (DS) concept [V. N. Goncharov et al., Novel Hot-Spot Ignition Designs for Inertial Confinement Fusion with Liquid-Deuterium-Tritium Spheres, Phys. Rev. Lett. 125, 065001 (2020).] for laser-driven inertial confinement fusion the deuterium-tritium fuel is initially in the form of a homogeneous liquid inside a wetted-foam spherical shell. This fuel is ignited using a conventional implosion, which is preceded by a initial compression of the fuel followed by its expansion and dynamic formation of a highdensity fuel shell with a low-density interior. This Letter reports on a scaled-down, proof-of-principle experiment on the OMEGA laser demonstrating, for the first time, the feasibility of DS formation. A shell is formed by convergent shocks launched by laser pulses at the edge of a plasma sphere, with the plasma itself formed as a result of laser-driven compression and relaxation of a surrogate plastic-foam ball target. Three x-ray diagnostics, namely, 1D spatially resolved self-emission streaked imaging, 2D self-emission framed imaging, and backlighting radiography, have shown good agreement with the predicted evolution of the DS and its stability to low Legendre mode perturbations introduced by laser irradiation and target asymmetries. Submitted for publication in Physical Review Letters

Energy Flow in Thin Shell Implosions and Explosions

2025-04-08T04:38:23Z

Energy Flow in Thin Shell Implosions and Explosions Ruby, J.J.; Rygg, J.R.; Chin, D.A.; Gaffney, J.A.; Adrian, Patrick J.; Forrest, C.J.; Glebov, Y.Yu.; Kabadi, Neel V.; Nilson, P.M.; Ping, Y.; Stoeckl, C.; Collins, G.W. Energy flow and balance in convergent systems beyond petapascal energy densities controls the fate of late-stage stars and the potential for controlling thermonuclear inertial fusion ignition. Timeresolved x-ray self-emission imaging combined with a Bayesian inference analysis is used to describe the energy flow and the potential information stored in the rebounding spherical shock at 0.22 petaPascal (2.2 Gbar or billions of atmospheres pressure). This analysis, together with a simple mechanical model, describes the trajectory of the shell and the time history of the pressure at the fuel-shell interface, ablation pressure, and energy partitioning including kinetic energy of the shell and internal energy of the fuel. The techniques used here provide a fully self-consistent uncertainty analysis of integrated implosion data, a thermodynamic-path independent measurement of pressure in the petaPascal range, and can be used to deduce the energy flow in a wide variety of implosion systems to petapascal energy densities. Submitted for publication in Physical Review Letters

Constraining Physical Models at Gigabar Pressures

2025-04-08T04:47:08Z

Constraining Physical Models at Gigabar Pressures Ruby, J.J.; Rygg, J.R.; Chin, D.A.; Gaffney, J.A.; Adrian, Patrick J.; Bishel, D.; Forrest, C.J.; Glebov, Y.Yu.; Kabadi, Neel V.; Nilson, P.M.; Ping, Y.; Stoeckl, C.; Collins, G.W. High-energy-density (HED) experiments in convergent geometry are able to test physical models at pressures beyond hundreds of millions of atmospheres. The measurements from these experiments are generally highly integrated and require unique analysis techniques to procure quantitative information. This work describes a methodology to constrain the physics in convergent HED experiments by adapting the methods common to many other fields of physics. As an example, a mechanical model of an imploding shell is constrained by data from a thin-shelled direct-drive exploding-pusher experiment on the OMEGA Laser System using Bayesian inference, resulting in the reconstruction of the shell dynamics and energy transfer during the implosion. The model is tested by analyzing synthetic data from a 1-D hydrodynamics code and is sampled using a Markov chain Monte Carlo to generate the posterior distributions of the model parameters. The goal of this work is to demonstrate a general methodology that can be used to draw conclusions from a wide variety of HED experiments. Submitted for publication in Physical Review E

Prospects of core–edge integrated no-ELM and small-ELM scenarios for future fusion devices

2025-04-08T04:27:15Z

Prospects of core–edge integrated no-ELM and small-ELM scenarios for future fusion devices Viezzer, E.; Austin, M.E.; Bernert, M.; Burrell, K.H.; Cano-Megias, P.; Chen, X.; Cruz-Zabala, D.J.; Coda, S.; Faitsch, M.; Fevrier, O.; Gil, L.; Giroud, C.; Happel, T.; Harrer, G.F.; Hubbard, Amanda E.; Hughes, Jerry W.; Kallenbach, A.; Labit, B.; Merle, A.; Meyer, H.; Paz-Soldan, C.; Oyola, P.; Sauter, O.; Siccinio, M.; Silvagni, D.; Solano, E.R.; EUROfusion WPTE and ASDEX Upgrade Teams One of our grand challenges towards fusion energy is the achievement of a high-performance plasma core coupled to a boundary solution. The high confinement mode (H-mode) provides such a high-performance fusion core due to the build-up of an edge transport barrier leading to a pedestal. However, it usually features type-I edge localized modes (ELMs) which pose a threat for long-duration plasma operation in future fusion devices as they induce large energy fluences onto the plasma facing components and typically are projected to damage the first wall. For future fusion devices, the integration of a stationary no-ELM regime with a power exhaust solution is indis- pensable. Several no-ELM and small-ELM regimes have extended their operational space in the past years, with the ultimate goal of providing an alternative core-edge solution to ITER and EU-DEMO. Prominent no-ELM or small-ELM alternatives include the I-mode, QH-mode, EDA H-mode, quasi-continuous exhaust (QCE) and ‘grassy’ ELM regimes, X-point radiator scenarios and negative triangularity L-mode. The state-of-the-art, including access conditions and main signatures, of these alternative regimes is reviewed. Many of these regimes partly match the operational space of ITER and EU-DEMO, however, knowledge gaps remain. Besides compatibility with divertor detachment and a radiative mantle, these include extrapolations to high Q operations, low core collisionality, high Greenwald fractions, impurity transport, amongst others. The knowledge gaps and possible strategies to close these gaps to show their applicability to ITER and EU-DEMO are discussed. Submitted for publication in Nuclear Materials and Energy

Scaling laws for electron kinetic effects in tokamak scrape-off layer plasmas

2025-04-07T09:18:13Z

Scaling laws for electron kinetic effects in tokamak scrape-off layer plasmas Power, D.; Mijin, S.; Wigram, Mike; Militello, F.; Kingham, R. Tokamak edge (scrape-off layer (SOL)) plasmas can exhibit non-local transport in the direction parallel to the magnetic field due to steep temperature gradients. This effect along with its consequences has been explored at equilibrium for a range of conditions, from sheath-limited to detached, using the 1D kinetic electron code SOL-KiT, where the electrons are treated kinetically and compared to a self-consistent fluid model. Line-averaged suppression of the kinetic heat flux (compared to Spitzer-Härm) of up to 50% is observed, contrasting with up to 98% enhancement of the sheath heat transmission coefficient, γe. Simple scaling laws in terms of basic SOL parameters for both effects are presented. By implementing these scalings as corrections to the fluid model, we find good agreement with the kinetic model for target electron temperatures. It is found that the strongest kinetic effects in γe are observed at low-intermediate collisionalities, and tend to increase (keeping upstream collisionality fixed) at increasing upstream densities and temperatures. On the other hand, the heat flux suppression is found to increase monotonically as upstream collisionality decreases. The conditions simulated encompass collisionalities relevant to current and future tokamaks. Submitted for publication in Nuclear Fusion

Editorial Foreward: Special Issue of Papers arising from the 18th International Workshop on H-mode Physics and Transport Barriers (Princeton, USA, 2022)

2025-04-08T04:33:49Z

Editorial Foreward: Special Issue of Papers arising from the 18th International Workshop on H-mode Physics and Transport Barriers (Princeton, USA, 2022) Hughes, Jerry W. This Special Issue of Nuclear Fusion collects papers from the 18th International Workshop on H-mode Physics and Transport Barriers, known more commonly as the 'H-mode Workshop', which was jointly hosted from 20–23 September 2022 by Princeton Plasma Physics Laboratory, Princeton University, Massachusetts Institute of Technology and General Atomics. The workshop was held as a hybrid event, with the on-site activities based at Princeton's Andlinger Center in Princeton, New Jersey, USA. It was the latest in a series of nominally biennial workshops beginning in 1987 and which have been hosted in a number of world locations (San Diego, Gut Ising, Abingdon, Naka, Princeton, Kloster Seeon, Oxford, Toki, St. Petersburg, Tsukuba, Fukuoka, Garching, Shanghai). Submitted for publication in Nuclear Fusion

Unitary Quantum Lattice Simulations for Maxwell Equations in Vacuum and in Dielectric Media

2025-04-08T04:43:08Z

Unitary Quantum Lattice Simulations for Maxwell Equations in Vacuum and in Dielectric Media Vahala, George; Valhala, Linda; Soe, Min; Ram, Abhay K. Utilizing the similarity between the spinor representation of the Dirac equation and the Maxwell equations that has been recognized since the early days of relativistic quantum mechanics, a quantum lattice (QLA) representation of unitary collision-stream operators of Maxwell’s equations is derived for both homogeneous and inhomogeneous media. A second order accurate 4-spinor scheme is developed and tested successfully for two dimensional (2D) propagation of a Gaussian pulse in a uniform medium while for normal (1D) incidence of an electromagnetic Gaussian wave packet onto a dielectric interface requires 8-component spinors. In particular, the well-known phase change, field amplitudes and profile widths are recovered by the QLA asymptotic profiles without the imposition of electromagnetic boundary conditions at the interface. The QLA simulations yield the time-dependent electromagnetic fields as the wave packet enters and straddles the dielectric boundary. QLA involves unitary interleaved non-commuting collision and streaming operators that can be coded onto a quantum computer – the non-commutation being the very reason why one perturbatively recovers the Maxwell equations. Submitted for publication in Journal of Physics

Combinatorial development of the low-density high-entropy alloy Al10Cr20Mo20Nb20Ti20Zr10 having gigapascal strength at 1000 C

2025-04-07T09:18:09Z

Combinatorial development of the low-density high-entropy alloy Al10Cr20Mo20Nb20Ti20Zr10 having gigapascal strength at 1000 C Waseem, Owais Ahmed; JinRyu, Ho A pseudo-ternary combinatorial approach to AlxTayVzCr20Mo20Nb20Ti20Zr10 revealed the composition of refractory high-entropy alloys characterized by outstanding high-temperature yield strength. Compression testing of Al10Cr20Mo20Nb20Ti20Zr10 disclosed yield strengths of 1206 MPa at 1000 °C, one of the highest values reported for refractory high-entropy alloys. Ta-containing AlxTayVzCr20Mo20Nb20Ti20Zr10 presented a lower high-temperature strength, while characterization of Al10Cr20Mo20Nb20Ti20Zr10 showed C14 Al2Zr- and NbCr2-type hexagonal Laves intermetallics, with a hardness of ∼10.5 GPa (higher than that of the body centered cubic phase, at ∼9 GPa). The stronger bonds between Al and transition metals appear to give rise to extraordinary load-bearing capabilities in Al10Cr20Mo20Nb20Ti20Zr10, at high temperatures. Owing to this rare combination of relatively low density (6.96 g/cm3) and remarkable high-temperature strength, Al10Cr20Mo20Nb20Ti20Zr10 has emerged as a potential material for high-temperature structural applications. Submitted for publication in Journal of Alloys and Compounds

Prediction of DIII-D Pedestal Structure from Externally Controllable Parameters

2025-04-08T04:13:48Z

Prediction of DIII-D Pedestal Structure from Externally Controllable Parameters Zeger, Emi U.; Laggner, Florian M.; Bortolon, Alessandro; Rea, Cristina; Meneghini, Orso; Saarelma, Samuli; Sammuli, Brian S.; Smith, Sterling P.; Zhao, Jinjin The sharp increase of pressure at the edge of a high confinement mode (H-mode) plasma, the pedestal, strongly impacts overall plasma performance. Predicting the pedestal is a necessity to control and optimize tokamak operations. An experimental data-driven machine learning (ML) approach is presented that predicts the pedestal heights and widths of electron density (ne) and electron temperature (Te) profiles as well as the separatrix ne from externally controllable parameters such as the plasma shape, heating method and power, and gas puff rate and integrated gas puff. The OMFIT framework was used with DIII-D data to efficiently, robustly, and automatically build a database of pedestal parameters to train machine learning models. Database creation was enabled by the search engine tool for DIII-D data, TokSearch, which parallelizes data fetching, enabling fast searches through basic signals of thousands of DIII-D shots and selection of relevant time intervals. Principal Component Analysis (PCA) separated the database into three clusters that represent classes of plasma shapes that are regularly used in DIII-D. The most important parameters for setting the pedestal structure were plasma current (Ip), toroidal magnetic field (Bφ), neutral beam heating power (PNBI) and shaping quantities. The Deep Jointly Informed Neural Networks (DJINN) algorithm was applied to identify suitable neural network (NN) architectures that appropriately capture the features of the pedestal database. Separate NNs were implemented for each pedestal parameter, and ensembling methods were used to improve the prediction accuracy and allowed estimation of the prediction uncertainty. The pedestal predictions of the test dataset lie within the measurement uncertainties of the pedestal parameters. The NN outperformed simple Linear Regression (LR) analysis, indicating non-linear dependencies in the pedestal structure. The presented achievements illustrate a promising path for future research, using feature extraction to infer experimental trends and thereby improve pedestal models as well as deploying NN for a fast pedestal prediction in DIII-D scenario development. Submitted for publication in IEEE Transactions on Plasma Science

Exploring the Effects of Partial Electrical Connectors on HTS Coils: A Case Study of Insulated Coil and Paraffin-Impregnated NI Coil

2025-04-08T04:37:32Z

Exploring the Effects of Partial Electrical Connectors on HTS Coils: A Case Study of Insulated Coil and Paraffin-Impregnated NI Coil Lee, Wooseung; Yang, Hongmin; Park, Dongkeun; Hwang, Young Jin; Im, Chaemin; Kim, Jaemin; Hahn, Seungyong; Lee, SangGap This study explores the influence of the Partial-Electrical-Connector (PEC) on High-Temperature Superconducting (HTS) coils. The PEC method emerges as a promising alternative to the conventional No-Insulation (NI) technique, establishing a direct current path between turns through partially soldered metal foils, such as copper, on the coil surface. This innovative approach achieves comparable performance to NI without necessitating a complete path between turns, offering advantages even in insulated or paraffin-impregnated coils. For the investigation, an insulated HTS coil and two NI HTS coils with paraffin impregnation are prepared. These coils undergo testing under overcurrent conditions, and their performance is compared with PEC-applied samples. The results demonstrate that coils with PEC application exhibit definitive current bypass characteristics. This finding highlights the potential of PEC to effectively create current bypass paths in both insulated and paraffin-impregnated coils. Submitted for publication in IEEE Transactions on Applied Superconductivity

Conceptual Design of a Portable, Solid-Nitrogen-Cooled 0.5-T/560-mm Point-of-Care MRI Magnet

2025-04-07T08:38:09Z

Conceptual Design of a Portable, Solid-Nitrogen-Cooled 0.5-T/560-mm Point-of-Care MRI Magnet Park, Dongkeun; Bascuñán, Juan; Lee, Wooseung; Iwasa, Yukikazu We describe the conceptual design of a portable, liquid-helium-free, all-REBCO, 0.5-T/560-mm point-of-care magnetic resonance imaging (MRI) magnet. It is free from an external power supply and a refrigeration system during operation. In our portable MRI magnet, we use a detachable “cryocirculator” that circulates, in a closed circuit, cold working fluid, and most importantly for portability, it can be readily coupled to or decoupled from the magnet, in contrast, a conventional cryocooler is mechanically attached to the magnet. Another unique feature of our system is a volume of solid nitrogen (SN2) in the cold chamber that adds enough thermal mass to the magnet in the 30–36-K operating temperature range, enabling it to maintain its field over a period of, for this system,≥10 hours, plenty enough for this portable MRI system, uncoupled from its cryocirculator, to perform its mission before it needs recooling. Submitted for publication in IEEE Transactions on Applied Superconductivity

Hot-Spot Modeling of REBCO NI Pancake Coil: Analytical and Experimental Approaches

2025-04-07T09:06:47Z

Hot-Spot Modeling of REBCO NI Pancake Coil: Analytical and Experimental Approaches Lee, Wooseung; Park, Dongkeun; Choi, Yoonhyuck; Li, Yi; Bascuana, Juan; Iwasa,Yukikazu The No-Insulation (NI) winding provides intrinsic bypassing current paths that enable self-protection from overheating. The self-protection of the NI coil is one of the most promising protection techniques for the high field hightemperature superconductor (HTS) magnet applications. Since the additional paths are valid for an HTS magnet with a thinner matrix, the self-protection mechanism is applicable even for the higher current density magnet with reduced matrix thickness inside the HTS tape. However, reducing the matrix can cause damage to the magnet by producing excessive heat during the quench. This research introduces a new modeling method to investigate the hot-spot characteristics in the REBCO NI pancake coil. The model is also validated with a sample NI HTS coil experiment result. Radial direction Normal Zone Propagation (NZP) velocity of the sample coil is estimated based on the suggested model. The calculated radial direction NZP velocity is applied to calculate the center field drop of the NI HTS coil, and the result is well-matched with the experiment result.We also introduce one example of the model applications. The maximum current density that will not exceed a given reference temperature in the adiabatic cooling condition is estimated using the model. Submitted for publication in IEEE Transactions on Applied Superconductivity

Hot-Spot Modeling of REBCO NI Pancake Coil: Analytical and Experimental Approaches

2025-04-07T09:06:29Z

Hot-Spot Modeling of REBCO NI Pancake Coil: Analytical and Experimental Approaches Lee, Wooseung; Park, Dongkeun; Choi, Yoonhyuck; Li, Yi; Bascuana, Juan; Iwasa,Yukikazu The No-Insulation (NI)winding provides intrinsic bypassing current paths that enable self-protection fromoverheating. The self-protection of the NI coil is one of the most promising protection techniques for the high field high-temperature superconductor (HTS) magnet applications. Since the additional paths are valid for an HTS magnet with a thinner matrix, the self-protection mechanism is applicable even for the higher current density magnet with reduced matrix thickness inside the HTS tape. However, reducing the matrix can cause damage to the magnet by producing excessive heat during the quench. This research introduces a new modeling method to investigate the hot-spot characteristics in the REBCO NI pancake coil. Themodel is also validated with a sample NI HTS coil experiment result. Radial direction Normal Zone Propagation (NZP) velocity of the sample coil is estimated based on the suggested model. The calculated radial direction NZP velocity is applied to calculate the center field drop of the NI HTS coil, and the result is well-matched with the experiment result.We also introduce one example of the model applications. The maximum current density that will not exceed a given reference temperature in the adiabatic cooling condition is estimated using the model. Submitted for publication in IEEE Transactions on Applied Superconductivity

Design of a Magnet and Gradient Coils for a Tabletop Liquid-Helium-Free, Persistent-Mode 1.5-T MgB2 Osteoporosis MRI

2025-04-08T04:38:35Z

Design of a Magnet and Gradient Coils for a Tabletop Liquid-Helium-Free, Persistent-Mode 1.5-T MgB2 Osteoporosis MRI Park, Dongkeun; Choi, Yoonhyuck; Li, Yi; Lee, Wooseung; Tanaka, Hiromi; Bascuñán, Juan; Ackerman, Jerome L.; Tanaka, Hideki; Iwasa, Yukikazu We have finalized the design of a full-scale tabletop 1.5-T/90-mm MgB2 finger MRI magnet system for osteoporosis screening based on our preliminary test results of small coils and superconducting joints.The magnet will operate in persistent mode at 10 K with an additional 5 K temperature margin. The magnet design which includes six main coils and an iron shield satisfies the required specification of a field intensity of 1.5T, homogeneity of≤5 ppm over a 20-mm diameter of spherical volume, and a fringe field of ≤5 gauss at 0.5 m in radius from the magnet center. An active protectionmethod using external heaters will be applied to prevent a local hot spot in the MgB2 windings from being overheated when quench occurs. Active shield transverse and axial gradient coils for this tabletop osteoporosis MRI, having primary and shield coil pairs, are designed to minimize stray fields that can induce eddy currents on nearby metal surface and thus imaging artifacts. This paper covers design and analysis of: 1) the main coils and iron shield; 2) coil former; 3) quench protection; and 4) active shield gradient coils.We also discuss design changes of the cryostat and equipment plan for the overall system. The magnet system will be completed and then, equipped with other MRI hardware components including an in-house-made gradient coil assembly and RF coils for demonstration of 1.5-T finger MRI in 2020. Submitted for publication in IEEE Transactions on Applied Superconductivity

Editorial: Using high energy density plasmas for nuclear experiments relevant to nuclear astrophysics

2025-04-07T23:59:35Z

Editorial: Using high energy density plasmas for nuclear experiments relevant to nuclear astrophysics Gatu Johnson, Maria; Hale, Gerald; Paris, Mark; Wiescher, Michael; Zylstra, Alex Editorial on the Research Topic Using high energy density plasmas for nuclear experiments relevant to nuclear astrophysics Submitted for publication in Frontiers in Physics

Simulations of divertor heat flux width using transport code with cross-field drifts under the BOUT++ framework

2025-04-07T08:30:45Z

Simulations of divertor heat flux width using transport code with cross-field drifts under the BOUT++ framework Li, N.M; Xu, X.Q.; Hughes, Jerry W.; Terry, James L.; Sun, J.Z.; Wang, D.Z. The fluid transport code [trans-electric field (Er) module] under the BOUT++ framework has been used to simulate divertor heat flux width and boundary Er with all drifts and the sheath potential in the scrape-off layer. The calculated steady state radial Er in the pedestal region has been compared with that of experimental measurements from the Alcator C-Mod tokamak. The magnitude and shape of Er are similar to those of the experimental data. In order to understand the relative role of cross-field drifts vs turbulent transport in setting the heat flux width, four C-Mod enhanced Dα H-mode discharges with a lower single null divertor configuration should be simulated. BOUT++ transport simulations with cross-field drifts included yield similar heat flux width λq to that of experimental measurements (within a factor of 2) from both the probe and the surface thermocouple diagnostics and show a similar trend with plasma current to that of the Eich experimental scaling. The simulations show that both drifts and turbulent transport compete to determine the heat flux width. The magnetic drifts play a dominant role in setting the divertor heat-flux width, while the E × B drift decreases the heat flux width by 10%–25%, leading to improved agreement with the experiment relative to Goldston’s model. A turbulence diffusivity scan (χ) identifies two distinct regimes: a drift dominant regime when χ is small and a turbulence dominant regime when χ is large. The Goldston heuristic drift model yields a lower limit of the width λq. Submitted for publication in AIP Advances

Overview of multiscale turbulence studies covering ion-to-electron scales in magnetically confined fusion plasma

2025-04-07T09:16:31Z

Overview of multiscale turbulence studies covering ion-to-electron scales in magnetically confined fusion plasma Maeyama, Shinya; Tokuzawa, Tokihiko; Howard, Nathan T.; Citrin, Jonathan; Watanabe, Tomo-Hiko Turbulent transport in magnetically confined fusion plasma has conventionally been analyzed at the ion gyroradius scale based on the microturbulence theory. However, ion-scale turbulence analysis sometimes fails to predict the turbulent transport flux observed experimentally. Microturbulence at the electron gyroradius scale and cross-scale interactions between disparate-scale turbulences are possible mechanisms to resolve this issue. This overview discusses the recent progress in multiscale turbulence studies and presents future perspectives from recent experimental, theoretical, and numerical investigations. The following aspects are highlighted: (1) the importance of electron-scale effects in experiments, (2) the physical mechanisms of cross-scale interactions, (3) modeling electron-scale effects in quasilinear transport models, and (4) the impacts of cross-scale interactions on burning plasmas. Understanding multiscale turbulence is necessary to improve performance prediction and explore optimal operations for future burning plasmas Submitted for publication in Nuclear Fusion

Using the Stix finite element RF code to investigate operation optimization of the ICRF antenna on Alcator C-Mod

2025-04-07T08:27:24Z

Using the Stix finite element RF code to investigate operation optimization of the ICRF antenna on Alcator C-Mod Migliore, Christina; Wright, John C.; Stowell, M.; Bonoli, Paul T. As the Ion Cyclotron Radio Frequency range (ICRF) heating becomes more favorable in fusion devices, the urgency of predicting and mitigating impurity generation that arises from it becomes more pressing. In the ICRF regime, rectified Radio Frequency (RF) sheaths are known to form at antenna and material edges that influence negative effects like sputtering and a decrease in heating efficiency. Methods to mitigate the formation of these RF sheaths through RF image currents cancellation have been experimentally studied. A power-phasing scan done on Alcator C-Mod in which the amount of power on the two inner straps (Pin) versus the total 4 straps (Ptot) was varied showed a minimization of enhanced potentials between Pin/Ptot ∼ 0.7–0.9 while impurities were minimized for Pin/Ptot ∼ 0.5–0.8. New capabilities in the realm of representing the RF sheath numerically now allow for these experiments to be simulated. Given the size of the sheath relative to the scale of the device, it can be approximated as a Boundary Condition (BC). A new parallelized cold-plasma wave equation solver called Stix implements a non-linear sheath impedance model BC formulated by Myra et al (2015 Phys. Plasmas 22 062507) through the method of finite elements using the MFEM library [http://mfem.org]. It is seen that Stix shows qualitative agreement with the measured C-Mod enhanced potentials. Submitted for publication in Nuclear Fusion

Dependence of the boundary heat flux width on core and edge profiles in Alcator C-Mod

2025-04-07T09:05:05Z

Dependence of the boundary heat flux width on core and edge profiles in Alcator C-Mod Ballinger, S.B.; Brunner, D.; Hubbard, Amanda E.; Hughes, Jerry W.; Kuang, Adam Q.; LaBombard, Brian; Terry, James L.; White, Anne E. This work presents new evidence that the heat flux width, λ q , in the Alcator C-Mod tokamak scales with the edge electron pressure, as observed in the ASDEX Upgrade (AUG) tokamak (Silvagni et al 2020 Plasma Phys. Control. Fusion 62 045015), but the scaling with volume-averaged pressure, p¯, from the plasma stored energy, found by Brunner et al (2018 Nucl. Fusion 58 094002), is a better predictor of λ q in Alcator C-Mod than the edge electron pressure. These previous studies, which find that λ q decreases with increasing plasma pressure, imply that a high performance core at high pressure will lead to challenging heat and particle exhaust due to very small λ q . This concern has led to our significant enlargement of the C-Mod database with the electron density, temperature, and pressure profile data from the Thomson scattering and electron cyclotron emission diagnostics. Using the C-Mod database augmented with new profile data, we find that λ q decreases with increasing edge electron pressure as λq∝ pe,95-0.26, similar to results from AUG, and showing the strength of cross-machine comparisons. We also find that λq∝ pe,core-0.56, consistent with the original finding from C-Mod that the heat flux width scales as p¯-0.48 (Brunner et al 2018 Nucl. Fusion 58 094002). The scalings of λ q with separatrix pressure and gradient scale length are found to match the AUG results qualitatively. The C-Mod scalings with edge plasma quantities have more scatter than the p¯ scaling, and, importantly, show different trends for H-modes relative to L- and I-mode. Investigating the source of this discrepancy presents an opportunity for further study that may improve our ability to predict the heat flux width in different confinement scenarios in the pursuit of optimizing core-edge performance in future reactors. Submitted for publication in Nuclear Fusion

Cross-code comparison of the edge codes SOLPS-ITER, SOLEDGE2D and UEDGE in modelling a low-power scenario in the DTT

2025-04-07T08:55:53Z

Cross-code comparison of the edge codes SOLPS-ITER, SOLEDGE2D and UEDGE in modelling a low-power scenario in the DTT Moscheni, M.; Meineri, C.; Wigram, Mike; Carati, C.; De Marchi, E.; Greenwald, M.; Innocente, P.; LaBombard, Brian; Subba, F.; Wu, H.; Zanino, R. As reactor-level nuclear fusion experiments are approaching, a solution to the power exhaust issue in future fusion reactors is still missing. The maximum steady-state heat load that can be exhausted by the present technology is around 10 MW m−2. Different promising strategies aiming at successfully managing the power exhaust in reactor-relevant conditions such that the limit is not exceeded are under investigation, and will be tested in the Divertor Tokamak Test (DTT) experiment. Meanwhile, the design of tokamaks beyond the DTT, e.g. EU-DEMO/ARC, is progressing at a high pace. A strategy to work around the present lack of reactor-relevant data consists of exploiting modelling to reduce the uncertainty in the extrapolation in the design phase. Different simulation tools, with their own capabilities and limitations, can be employed for this purpose. In this work, we compare SOLPS-ITER, SOLEDGE2D and UEDGE, three state-of-the-art edge codes heavily used in power exhaust studies, in modelling the same DTT low-power, pure-deuterium, narrow heat-flux-width scenario. This simplified, although still reactor-relevant, testbed eases the cross-comparison and the interpretation of the code predictions, to identify areas where results differ and develop understanding of the underlying causes. Under the conditions investigated, the codes show encouraging agreement in terms of key parameters at both targets, including peak parallel heat flux (1%–45%), ion temperature (2%–19%), and inner target plasma density (1%–23%) when run with similar input. However, strong disagreement is observed for the remaining quantities, from 30% at outer mid-plane up to a factor 4–5 at the targets. The results primarily reflect limitations of the codes: the SOLPS-ITER plasma mesh not reaching the first wall, SOLEDGE2D not including ion-neutral temperature equilibration, and UEDGE enforcing a common ion-neutral temperature. Potential improvements that could help enhance the accuracy of the code models for future applications are also discussed. Submitted for publication in Nuclear Fusion

Development and experimental qualification of novel disruption prevention techniques on DIII-D

2025-04-07T08:32:49Z

Development and experimental qualification of novel disruption prevention techniques on DIII-D Barr, J.L.; Sammuli, B.; Humphreys, D.A.; Olofsson, E.; Du, X.D.; Rea, Cristina; Wehner, W.P.; Boyer, M.D.; Eidietis, N.W.; Granetz, R.; Hyatt, A.; Liu, T.; Logan, N.; Munaretto, S.; Strait, E.; Wang, Z.R.; The DIII-D Team Novel disruption prevention solutions spanning a range of control regimes are being developed and tested on DIII-D to enable ITER success. First, a new real-time control algorithm has been developed and tested for regulating nearness to stability limits and maintaining safety-margins. Its first application has been for reliable prevention of vertical displacement events (VDEs) by adjusting plasma elongation (κ) and the inner-gap between the plasma and inner-wall in response to real- time open-loop VDE growth rate (γ) estimators. VDEs were robustly prevented up to average open-loop growth rates of 800 rad/s with initial tunings, with only applying shape modification when near safety limits. Second, the disruption risk during fast, emergency shutdown after large tearing and locked modes can be significantly improved by transitioning to a limited topology during shutdown. More than 50% of emergency limited shutdowns after locked modes reach a final normalized current I N < 0.3 before terminating, scaling to the 3 MA ITER requirement. This is in contrast to diverted shutdowns, the majority of which disrupt at I N > 0.8. Despite improvements, these results highlight the critical importance of early prevention. Third, a novel emergency shut down method has been developed which excites instabilities to form a warm, helical core post-thermal quench. The current quench extends to ~100ms and avoids VDEs and runaway electron generation. Novel real-time machine learning disruption prediction has been integrated with the DIII-D proximity controller, and a real- time compatible multi-mode MHD spectroscopy technique has been developed. Results presented here were enabled by a focused effort, the Disruption Free Protocol, in DIII-D’s 2019-20 campaign to complement disruption prevention experiments with a large piggy-back program. In addition to testing novel techniques, it is estimated to have helped avoid 32 potential disruptions in piggyback operations with rapid, early shutdowns after large rotating n=1 or locked modes. Submitted for publication in Nuclear Fusion

Dimensionless Parameter Scaling of Intrinsic Torque in C-Mod Enhanced Confinement Plasmas

2025-04-08T04:52:06Z

Dimensionless Parameter Scaling of Intrinsic Torque in C-Mod Enhanced Confinement Plasmas Rice, John E.; Cao, N.M.; Tala, T.; Chrystal, C.; Greenwald, M.J.; Hughes, Jerry W.; Marmar, E.S.; Reinke, M.L.; Rodriguez Fernandez, Pablo; Salmi, A. A dimensionless parameter dependence study of intrinsic torque has been performed on a database of H- and I-mode plasmas from the Alcator C-Mod tokamak. The torque was determined by comparing intrinsic angular momentum density profiles just before and just after L-H and L-I transitions. The intrinsic torque has been found to scale as beta_N^1.5 rho_*^-1.0 nu_$^0.1, with the parameter ranges 0.3 < beta_N <1.5, 0.004 < rho_* < 0.011 and 0.04 < nu_* < 0.9. Comparison with results from other tokamaks suggests that the intrinsic torque should be normalized by some measure of the device size. Submitted for publication in Nuclear Fusion

A semi-supervised machine learning detector for physics events in tokamak discharges

2025-04-07T08:29:36Z

A semi-supervised machine learning detector for physics events in tokamak discharges Montes, Kevin J.; Rea, Cristina; Tinguely, R. Alex; Sweeney, Ryan; Zhu, Jinxiang; Granetz, Robert Databases of physics events have been used in various fusion research applications, including the development of scaling laws and disruption avoidance algorithms, yet they can be time-consuming and tedious to construct. This paper presents a novel application of the label spreading semi-supervised learning algorithm to accelerate this process by detecting distinct events in a large dataset of discharges, given few manually labeled examples. A high detection accuracy (>85%) for H-L back transitions and initially rotating locked modes is demonstrated on a dataset of hundreds of discharges from DIII-D with manually identified events for which only 3 discharges are initially labeled by the user. Lower yet reasonable performance (~75%) is also demonstrated for the core radiative collapse, an event with a much lower prevalence in the dataset. Additionally, analysis of the performance sensitivity indicates that the same set of algorithmic parameters is optimal for each event. This suggests that the method can be applied to detect a variety of other events not included in this paper, given that the event is well described by a set of 0D signals robustly available on many discharges. Procedures for analysis of new events are demonstrated, showing automatic event detection with increasing fidelity as the user strategically adds manually labeled examples. Detections on Alcator C-Mod and EAST are also shown, demonstrating the potential for this to be used on a multi-tokamak dataset. Submitted for publication in Nuclear Fusion

Electron acceleration in laboratory-produced turbulent collisionless shocks

2025-04-07T09:03:50Z

Electron acceleration in laboratory-produced turbulent collisionless shocks Fiuza, F.; Swadling, G.F.; Grassi, A.; Rinderknecht, H.G.; Higginson, D.P.; Ryutov, D.D.; Bruulsema, C.; Drake, R.P.; Funk, S.; Glenzer, S.; Gregori, G.; Li, Chi-Kang; Pollock, B.B.; Remington, B.A.; Ross, J.S.; Rozmus, W.; Sakawa, Y.; Spitkovsky, A.; Wilks, S.; Park, H.-S. Astrophysical collisionless shocks are among the most powerful particle accelerators in the Universe. Generated by violent interactions of supersonic plasma flows with the interstellar medium, supernova remnant shocks are observed to amplify magnetic fields and accelerate electrons and protons to highly relativistic speeds. In the well-established model of diffusive shock acceleration, relativistic particles are accelerated by repeated shock crossings. However, this requires a separate mechanism that pre-accelerates particles to enable shock crossing. This is known as the ‘injection problem’, which is particularly relevant for electrons, and remains one of the most important puzzles in shock acceleration6. In most astrophysical shocks, the details of the shock structure cannot be directly resolved, making it challenging to identify the injection mechanism. Here we report results from laser-driven plasma flow experiments, and related simulations, that probe the formation of turbulent collisionless shocks in conditions relevant to young supernova remnants. We show that electrons can be effectively accelerated in a first-order Fermi process by small-scale turbulence produced within the shock transition to relativistic non-thermal energies, helping overcome the injection problem. Our observations provide new insight into electron injection at shocks and open the way for controlled laboratory studies of the physics underlying cosmic accelerators. Submitted for publication in Nature Physics

Evolution in microstructure and hardness of Titanium-Zirconium-Molybdenum (TZM) alloy after depth marker implantation for erosion diagnostic in fusion devices

2025-04-07T09:22:53Z

Evolution in microstructure and hardness of Titanium-Zirconium-Molybdenum (TZM) alloy after depth marker implantation for erosion diagnostic in fusion devices Waseem, Owais Ahmed; Woller, Kevin Benjamin A depth marker by ion implantation has been used for analysis of erosion on plasma-facing materials in fusion experiments. To assess the impact of ion implantation on the surface properties of these materials under investigation, Titanium-Zirconium-Molybdenum (TZM) alloy was irradiated with 4.8 MeV F3+ ions up to 1.04x1017 cm-2 at 330oC, achieving a depth marker centroid at ∼1.5 μm. After implantation, there is no significant change in microstructure and surface roughness under these implantation conditions, which were used for samples positioned on the high field side in the Experimental Advanced Superconducting Tokamak (EAST) device for erosion analysis. Nanoindentation measurements indicate an increase in hardness from ∼5.5 GPa to ∼6.6 GPa in the first 300 nm of the surface, within the eroded zone over a full years experimental campaign. Within 1.5 μm of the surface, where the damage from the ion beam is expected to be generated, the microstructure of implanted TZM shows a large number of dislocation lines (i.e. 1.0x109 dislocations/mm2), determined from TEM analysis, which can account for the increase in hardness of implanted TZM. These changes due to the ion implantation, though minor, should be considered when using ion implanted depth markers for erosion measurements of plasma-facing materials. Submitted for publication in Materials Chemistry and Physics

Development of Compact Tokamak Fusion Reactor Use Cases to Inform Future Transport Studies

2025-04-08T04:39:54Z

Development of Compact Tokamak Fusion Reactor Use Cases to Inform Future Transport Studies Holland, C.; Bas, E.M.; Orlov, D.M.; McClenaghan, J.; Lyons, B.; Grierson, B.A.; Jian, X.; Howard, Nathan T.; Rodriguez-Fernandez, Pablo The OMFIT STEP [O. Meneghini et al., Nucl. Fusion 10 1088 (2020)] workflow has been used to develop inductive and steady-state H-mode core plasma scenario use cases for a B0 = 8T, R0 = 4m machine in order to help guide and inform future higher- fidelity studies of core transport and confinement in compact tokamak reactors. Both use cases are designed to produce 200 MW or more of net electric power in an up- down symmetric plasma with minor radius a = 1.4 m, elongation κ = 2.0, triangularity δ = 0.5, and effective charge Zeff ≃ 2. Additional considerations based on the need for compatibility of the core with reactor-relevant power exhaust solutions and external actuators were used to guide and constrain the use case development. An extensive characterization of core transport in both scenarios is presented, the most important feature of which is the extreme sensitivity of the results to the quantitative stiffness level of the transport model used as well as the predicted critical gradients. This sensitivity is shown to arise from different levels of transport stiffness exhibited by the models, combined with the gyroBohm-normalized fluxes of the predictions being an order of magnitude larger than other H-mode plasmas. Additionally, it is shown that although heating in both plasmas is predominantly to the electrons and collisionality is low, the plasmas remain sufficiently well-coupled for the ions to carry a significant fraction of the thermal transport. As neoclassical transport is negligible in these conditions, this situation inherently requires long-wavelength ion gyroradius-scale turbulence to be the dominant transport mechanism in both plasmas. These results are combined with other basic considerations to propose a simple heuristic model of transport in reactor-relevant plasmas, along with simple metrics to quantify coupling and core transport properties across burning and non-burning plasmas. Submitted for publication in Journal of Plasma Physics

Impact of lithium wall conditioning and wave-frequency on high density lower hybrid current drive experiment on EAST

2025-04-07T09:21:56Z

Impact of lithium wall conditioning and wave-frequency on high density lower hybrid current drive experiment on EAST Baek, Seung Gyou; Li, M.H.; Wallace, Greg M.; Bonoli, Paul T.; Choi, W.; Ding, B.J.; Gao, W.; Gong, X.; Li, Y.C.; Lin, S.; Meng, L.; Poli, F.; Shiraiwa, S.; Wang, M.; Wang, Y.F.; Wu, C.B.; Wang, L.; Zang, Q.; Zhao, H. A series of dedicated lower hybrid current drive (LHCD) experiments on EAST shows that lithium wall conditioning extends LH current drive and heating up to the line-averaged density of n ̅_e≈ 4x1019 m-3 for both 2.45 and 4.6 GHz. Current drive at such a high density is crucial for the development of long-pulse non-inductive scenarios on EAST. With lithiation, the LH power injection of 1.5 MW at 2.45 GHz resulted in a drop of loop voltage of ~ 0.3 V, which is a comparable loop voltage drop observed with 1.1 MW at 4.6 GHz. The observed decrease in loop voltage is attributed mostly to the RF heating effect. Another LHCD experiment suggests that lithium wall coating has a more significant impact on the scrape-off-layer (SOL) properties than changes in the Greenwald fraction. LHCD at 2.45 GHz still suffers from a loss of efficiency. Enhanced power ionization in front of the launcher may cause the onset of density-dependent wave instabilities. The rise in the midplane SOL density may also accelerate a transition in the divertor regime, leading to additional ionization and collisional losses in the X-point divertor plasma. Ray-tracing modeling supports that a lower wave frequency is more prone to collisional power loss. The experiments confirm that lithiation is a useful tool to control the SOL plasma, and suggest that density control in front of the launcher may be critical to mitigating power loss mechanisms in the plasma boundary. Submitted for publication in Journal of Nuclear Materials

Design considerations for an ultrahigh-bandwidth Phase Contrast Imaging system applied to fusion grade devices

2025-04-08T04:52:34Z

Design considerations for an ultrahigh-bandwidth Phase Contrast Imaging system applied to fusion grade devices Marinoni, Alessandro; Rost, Jon C.; Porkolab, Miklos The PCI diagnostic is an internal reference interferometer that creates an image of absolutely calibrated electron density fluctuations integrated along the line of sight of the probing light beam. While conventional PCI diagnostics installed on fusion experiments worldwide employ light of wavelength equal to 10.59 μm, the same system using light at 1.55 μm wavelength would extend the spectral response in wave-number and frequency by factors of seven and over one hundred, respectively, thereby potentially providing quantitative measurements of the internal structure of density perturbations induced by either turbulent or radio-frequency waves, simultaneously covering ion to electron gyro-radius scales up to the GHz frequency region. Based on a previously developed 1.55 μm PCI prototype system, constraints to the design for such a diagnostic in fusion grade devices are presented and compared to those faced with the conventional method. Submitted for publication in Journal of Instrumentation

Quantifying experimental edge plasma evolution via multidimensional adaptive Gaussian process regression

2025-04-07T08:25:59Z

Quantifying experimental edge plasma evolution via multidimensional adaptive Gaussian process regression Mathews, Abhilash; Hughes, Jerry W. The edge density and temperature of tokamak plasmas are strongly correlated with energy and particle confinement and their quantification is fundamental to understanding edge dynamics. These quantities exhibit behaviours ranging from sharp plasma gradients and fast transient phenomena (e.g. transitions between low and high confinement regimes) to nominal stationary phases. Analysis of experimental edge measurements therefore require robust fitting techniques to capture potentially stiff spatiotemporal evolution. Additionally, fusion plasma diagnostics inevitably involve measurement errors and data analysis requires a statistical framework to accurately quantify uncertainties. This paper outlines a generalized multidimensional adaptive Gaussian process routine capable of automatically handling noisy data and spatiotemporal correlations. We focus on the edge-pedestal region in order to underline advancements in quantifying time-dependent plasma profiles including transport barrier formation on the Alcator C-Mod tokamak. Submitted for publication in IEEE Transactions on Plasma Science

Self-Protection Characteristic Comparison Between No-Insulation, Metal-as-Insulation, and Surface-Shunted-Metal-as-Insulation REBCO Coils

2025-04-07T08:32:10Z

Self-Protection Characteristic Comparison Between No-Insulation, Metal-as-Insulation, and Surface-Shunted-Metal-as-Insulation REBCO Coils Kim, Junseong; Park, Dongkeun; Dong, Fangliang; Lanzrath, Andrew; Lee, Wooseung; Bascuñán, Juan; Iwasa, Yukikazu The metal tape co-winding or a metal-as-insulation (MI) winding method is an excellent way to improve the mechanical properties and reduce the average current density, thereby decreasing the stress in high-field REBCO magnet without completely losing the benefits of the no-insulation (NI) winding method. However, the MI winding increases the resistance between turns, which is known as characteristic resistance. The increased characteristic resistance can reduce the bypass current during abnormal transition situation, such as quench, which may not be desirable from a magnet protection point of view. To take advantage of both the MI and NI winding, one possible solution to reduce characteristic resistance of the MI winding coils is to add a shunt on top of the winding surface of the coil. We call this method surface-shunted-metal-as-insulation (SSMI). In this presentation, we compare the characteristic resistances and their correlated selfprotecting characteristics between NI, MI, and SSMI. We present the test results of single pancake coils which wound using different winding methods (NI, MI, and SSMI) with same winding pressure of 20 N. In particular, we investigated how the SSMImethod affects the characteristic resistance. Submitted for publication in IEEE Transactions on Applied Superconductivity

Self-Protection Characteristic Comparison Between No-Insulation, Metal-as-Insulation, and Surface-Shunted-Metal-as-Insulation REBCO Coils

2025-04-07T08:30:03Z

Sudden-Discharging Quench Dynamics in a No-Insulation Superconducting Coil

2025-04-07T09:08:46Z

Sudden-Discharging Quench Dynamics in a No-Insulation Superconducting Coil Dong, Fangliang; Park, Dongkeun; Kim, Junseong; Bacuñán, Juan; Iwasa, Yukikazu It is generally agreed that no-insulation (NI) hightemperature superconducting (HTS) magnets do not quench because of the turn-to-turn energy-releasing bypass unique to NI. However, these magnets, especially with high operating current and low ambient thermal capacity, still occur unexpected quenches when the current through the magnets suddenly drops to zero (i.e., the sudden-discharging quench). Here, we report this kind of quench, which is different from that widely-reported quench happening during charging (i.e., the energizing quench). Here, a demonstrative coil with 655-turns, 350 A operating current, and 4 K conduction cooling, is used to prove this sudden-discharging quench, and a simulationmodel is built to reveal the quench dynamics. Results show the turn-to-turn heat triggers the initial partial quench in the inner coil turns and then the induced overcurrent spreads out the quench like an avalanche to the outer coil turns. Submitted for publication in IEEE Transactions on Applied Superconductivity

Observations of multi-ion physics and kinetic effects in a surrogate to the solar CNO reactions

2025-04-08T04:53:54Z

Observations of multi-ion physics and kinetic effects in a surrogate to the solar CNO reactions Jeet, J.; Zylstra, A.B.; Gatu Johnson, Maria; Kabadi, Neel V.; Adrian, Patrick J.; Forrest, C.; Glebov, V. The ‘CNO process’ occurs in heavier stars with finite metallicity in which hydrogen burning is catalyzed in the presence of 12C. These reactions are more strongly dependent on temperature than the pp cycle reactions, and thus the CNO cycle dominates only in massive stars. For these types of reactions to be studied at ICF facilities such as OMEGA, an implosion platform using heavier nuclei in the fuel and capable of creating ion temperatures on the order of at least 20 keV is required. A potential route to reach these conditions is to take advantage of kinetic effects in low-convergence shock-driven ‘exploding pusher’ implosions. In this experiment, shots were conducted at the OMEGA laser facility using the surrogate reaction 13C + D. Its cross section is substantially higher than the actual astrophysical CNO reactions. The yield of this reaction in these implosions was much lower than expected. Physical explanations are discussed, with significant species stratification the likely explanation. Submitted for publication in High Energy Density Physics

Brazing characteristics, microstructure, and wettability of laser powder bed fusion additive manufactured GRCop-84 compared to CuCrZr and OFC, and brazing to titanium-zirconium-molybdenum alloy limiters

2025-04-08T04:24:55Z

Brazing characteristics, microstructure, and wettability of laser powder bed fusion additive manufactured GRCop-84 compared to CuCrZr and OFC, and brazing to titanium-zirconium-molybdenum alloy limiters Seltzman, Andrew H.; Wukitch, S.J. Laser Powder Bed Fusion (L-PBF) of Glenn Research Copper 84 (GRCop-84), a Cr2Nb (8 at. % Cr, 4 at. % Nb) precipitation hardened alloy, produces a fully dense, high conductivity alloy with a yield strength of 500 MPa and ultimate tensile strength (UTS) of 740 MPa with 20% elongation; superior to other competing copper alloys. Braze wetting characteristics of GRCop-84 with Ag-Cu-X, and Au-Cu brazes were similar to CuCrZr, but less than oxygen free copper. No difference in wetting was observed between infill and surface contour areas in L-PBF GRCop-84. Wet sanding to 240 grit (Ra=0.24 µm) was considered the optimal surface condition. Silver diffusing through GRCop-84 depleted Cr2Nb precipitates from the copper grain and deposited agglomerations of coarsened precipitates within silver-rich regions of intergranular diffusion once a density threshold was reached. Microstructure modification was minimized with 50Au-50Cu braze implying that silver caused precipitate coarsening and agglomeration, and not high temperature exposure. Coarsened precipitates were observed on the surface within braze pools implying a contribution to braze wetting. Palcusil-25, Ticusil, CuSil-ABA, and 50Au-50Cu brazes were suitable for brazing to unplated Titanium-Zirconium-Molybdenum (TZM), while sulfamate nickel plating to allows wetting with CuSil or other non-active brazes. Vacuum brazing techniques were developed to join a 1 mm thick layer of TZM to the front of additive manufactured GRCop-84 waveguides considering the brazing characteristics of both GRCop-84, TZM, and internal stress from the difference in coefficient in thermal expansion. Submitted for publication in Fusion Engineering and Design

Towards the first plasma-electron screening experiment

2025-04-08T04:12:52Z

Towards the first plasma-electron screening experiment Casey, Daniel T.; Weber, Chris R.; Zylstra, Alex B.; Cerjan, Charlie J.; Hartouni, Ed; Hohenberger, Matthias; Divol, Laurent; Dearborn, David S.; Kabadi, Neel V.; Lahmann, Brandon; Gatu Johnson, Maria; Frenje, Johan A. The enhancement of fusion reaction rates in a thermonuclear plasma by electron screening of the Coulomb barrier is an important plasma-nuclear effect that is present in stellar models but has not been experimentally observed. Experiments using inertial confinement fusion (ICF) implosions may provide a unique opportunity to observe this important plasma-nuclear effect. Herein, we show that experiments at the National Ignition Facility (NIF) have reached the relevant physical regime, with respect to the density and temperature conditions, but the estimated impacts of plasma screening on nuclear reaction rates are currently too small and need to be increased to lower the expected measurement uncertainty. Detailed radiation hydrodynamics simulations show that practical target changes, like adding readily available high-Z gases, and significantly slowing the inflight implosion velocity, while maintaining inflight kinetic energy, might be able to push these conditions to those where plasma screening effects may be measurable. We also perform synthetic data exercises to help understand where the anticipated experimental uncertainties will become important. But challenges remain, such as the detectability of the reaction products, non-thermal plasma effects, species separation, and impacts of spatial and temporal gradients. This work lays the foundation for future efforts to develop an important platform capable of the first plasma electron screening observation. Submitted for publication in Frontiers in Physics

Transport of High-energy Charged Particles through Spatially Intermittent Turbulent Magnetic Fields

2025-04-08T04:19:08Z

Transport of High-energy Charged Particles through Spatially Intermittent Turbulent Magnetic Fields Chen, L.E.; Bott, A.F.A.; Tzeferacos, P.; Rigby, A.; Bell, A.; Bingham, R.; Graziani, C.; Katz, J.; Koenig, M.; Li, Chi-Kang; Petrasso, Richard D.; Park, H.-S.; Ross, J.S.; Ryu, D.; White, T.G.; Reville, B.; Matthews, J.; Meinecke, J.; Miniati, F.; Zweibel, E.G.; Sarkar, S.; Schekochihin, A.A.; Lamb, D.Q.; Froula, D.H.; Gregori, G. Identifying the sources of the highest energy cosmic rays requires understanding how they are deflected by the stochastic, spatially intermittent intergalactic magnetic field. Here we report measurements of energetic charged- particle propagation through a laser-produced magnetized plasma with these properties. We characterize the diffusive transport of the particles experimentally. The results show that the transport is diffusive and that, for the regime of interest for the highest energy cosmic rays, the diffusion coefficient is unaffected by the spatial intermittency of the magnetic field. Submitted for publication in Astrophysical Journal

Understanding LOC/SOC Phenomenology in Tokamaks

2025-04-07T08:30:43Z

Understanding LOC/SOC Phenomenology in Tokamaks Rice, John E.; Citrin, J.; Cao, N.M.; Diamond, P.H.; Fable, E.; Greenwald, M.; Grierson, B.A. Phenomenology of Ohmic energy confinement saturation in tokamaks is reviewed. Characteristics of the linear Ohmic confinement (LOC) and saturated Ohmic confinement (SOC) regimes are documented and transformations in all transport channels across the LOC/SOC transition are described, including rotation reversals, ``non-local'' cut-off and density peaking, in addition to dramatic changes in fluctuation intensity. Unification of results from nearly 20 devices indicates that the LOC/SOC transition occurs at a critical value of the product of the density, edge safety factor and device major radius, and that this product increases with toroidal magnetic field. Comparison with gyro-kinetic simulations suggests that the effects of sub-dominant TEMs are important in the LOC regime while ITG mode turbulence dominates with SOC. Submitted for publication in Nuclear Fusion

Design of inertial fusion implosions reaching the burning plasma regime

2025-04-08T04:34:34Z

Design of inertial fusion implosions reaching the burning plasma regime Kritcher, A.L.; Young, C.V.; Robey, H.F.; Weber, C.R.; Zylstra, A.B.; Hurricane, O.A.; Callahan, D.A.; Ralph, J.E.; Ross, J.S.; Baker, K.L.; Casey, D.T.; Clark, D.S.; Döeppner, T.; Divol, L.; Hohenberger, M.; Le Pape, S.; Pak, A.E.; Patel, P.K.; Tommasini, R.; Ali, S.J.; Amendt, P.A.; Atherton, J.; Bachmann, B.; Bailey, D.; Benedetti, L.R.; Berzak Hopkins, L.; Betti, R.; Bhandarkar, S.D.; Bionta, R.M.; Birge, N.W.; Bond, E.J.; Bradley, D.K.; Braun, T.; Briggs, T.M.; Bruhn, M.W.; Celliers, P.M.; Chang, B.; Chapman, T.; Chen, H.; Choate, C.; Christopherson, A.R.; Crippen, J.W.; Dewald, E.L.; Dittrich, T.R.; Edwards, M.J.; Farmer, W.A.; Field, J.E.; Fittinghoff, D.; Frenje, Johan A.; Gaffney, J.; Gatu Johnson, Maria; Glenzer, S.H.; Grim, G.P.; Haan, S.; Hahn, K.D.; Hall, G.N.; Hammel, B.A.; Harte, J.; Hartouni, E.; Heebner, J.E.; Hernandez, V.J.; Herrmann, H.; Herrmann, M.C.; Hinkel, D.E.; Ho, D.D.; Holder, J.P.; Hsing, W.W.; Huang, H.; Humbird, K.D.; Izumi, N.; Jeet, J.; Jones, O.; Kerbel, G.D.; Kerr, S.M.; Khan, S.F.; Kilkenny, J.; Kim, Y.; Geppert Kleinrath, H.; Geppert Kleinrath, V.; Kline, J.L.; Kong, C.; Koning, J.M.; Kroll, J.J.; Landen, O.L.; Langer, S.; Larson, D.; Lemos, N.C.; Lindl, J.D.; Ma, T.; MacGowan, B.J.; Mackinnon, A.J.; MacLaren, S.A.; MacPhee, A.G.; Marinak, M.M.; Mariscal, D.A.; Marley, E.V.; Masse, L.; Meaney, K.; Meezan, N.B.; Michel, P.A.; Millot, M.A.; Milovich, J.L.; Moody, J.D.; Moore, A.S.; Morton, J.W.; Newman, K.; Di Nicola, J.-M. G.; Nikroo, A.; Nora, R.; Patel, M.V.; Pelz, L.J.; Peterson, J.L.; Ping, Y.; Pollock, B.B.; Ratledge, M.; Rice, N.G.; Rinderknecht, H.; Rosen, M.; Rubery, M.S.; Salmonson, J.D.; Sater, J.; Schiaffino, S.; Schlossberg, D.J.; Schneider, M.B.; Schroeder, C.R.; Scott, H.A.; Sepke, S.M.; Sequoia, K.; Sherlock, M.W.; Shin, S.; Smalyuk, V.A.; Spears, B.K.; Springer, P.T.; Stadermann, M.; Stoupin, S.; Strozzi, D.J.; Suter, L.J.; Thomas, C.A.; Town, R.P.J.; Tubman, E.R.; Volegov, P.L.; Widmann, K.; Wild, C.; Wilde, C.H.; Van Wonterghem, B.M.; Woods, D.T.; Woodworth, B.N.; Yamaguchi, M.; Yang, S.T.; Zimmerman, G.B. One of the last remaining milestones in fusion research before reaching ignition is creating a burning plasma state, where alpha particles from deuterium-tritium (DT) fusion reactions redeposit their energy as the dominant source of heating in the plasma. The indirect-drive inertial confinement fusion approach at the National Ignition Facility (NIF) uses a laser-generated radiation cavity (hohlraum) to spherically implode DT fuel to high temperatures and densities in a central ”hot spot”. Here, we deliver more energy to the hot spot than ever before, while maintaining the extreme pressures required for inertial confinement, by increasing the size of the implosion compared to previous experiments. We develop more efficient hohlraums, to drive these larger implosions within NIF’s current laser energy and power capability and control symmetry by moving energy between laser beams and by changing the shape of the hohlraum. These designs resulted in record fusion powers of 1.5 petawatts, greater than the input power of the laser, and 170 kJ of fusion energy. Radiation hydrodynamics simulations show alpha particle heating as the dominant term in the hot spot energy balance, e.g. a burning plasma state. This work is expected to motivate future studies of burning plasmas and improve predictive capability by providing a benchmark for modeling used to understand the proximity to ignition. Submitted for publication in Nature Physics

Collisional effects on resonant particles in quasilinear theory

2025-04-07T08:27:43Z

Collisional effects on resonant particles in quasilinear theory Catto, Peter J. A careful examination of the effects of collisions on resonant wave-particle interactions leads to an alternate interpretation and deeper understanding of the quasilinear operator originally formulated by Kennel and Engelmann (Phys. Fluids vol. 9, 1966, pp. 2377- 2388) for collisionless, magnetized plasmas, and widely used to model radio frequency heating and current drive. The resonant and nearly resonant particles are particularly sensitive to collisions that pitch angle scatter them out of and into resonance. As a result, the resonant particle-wave interactions occur in the center of a narrow collisional boundary when the collision frequency nu is very small compared to the wave frequency omega. The diffusive nature of the pitch angle scattering combined with the wave-particle resonance condition enhances the collision frequency by (omega/nu)2/3 >>1, resulting in an effective resonant particle collision time of tau_int ~ (nu /omega)2/3 nu <<1/ nu . A rigorous collisional boundary layer analysis generalizes the standard quasilinear operator to a form that is fully consistent with Kennel-Englemann, but allows replacing the delta function appearing in the diffusivity with a simple integral (having the appropriate delta function limit) retaining the new physics associated with the narrow boundary layer, while preserving the entropy production principle. The limitations of the collisional boundary layer treatment are also estimated, and indicate that substantial departures from Maxwellian are not permitted. Submitted for publication in Journal of Plasma Physics

Combinatorial synthesis and analysis of AlxTayVz-Cr20Mo20Nb20Ti20Zr10 and Al10CrMoxNbTiZr10 refractory high-entropy alloys: Oxidation behavior

2025-04-08T04:27:11Z

Combinatorial synthesis and analysis of AlxTayVz-Cr20Mo20Nb20Ti20Zr10 and Al10CrMoxNbTiZr10 refractory high-entropy alloys: Oxidation behavior Waseem, Owais Ahmed; Ryu, Ho Jin The combinatorial development of refractory high-entropy alloy AlxTayVz-Cr20Mo20Nb20Ti20Zr10 (AlxTayVz-Q) was carried out, and microstructural analysis was performed. The homogenized AlxTayVz-Q revealed a body-centered cubic structure with intermetallic phases. High-temperature oxidation analysis of AlxTayVz-Q for 1 h at 1000 °C using thermogravimetric analysis (TGA) revealed volatile oxidation of the alloy. Therefore, in an effort to improve the oxidation resistance of the alloy, the composition was modified to Al10CrMoxNbTiZr10 and analyzed. The TGA analysis revealed enhanced oxidation resistance of Al10CrNbTiZr10 (Mo-0), and a weight gain of only 1 mg/cm2 after oxidation for 1 h at 1000 °C in air, owing to the formation of the protective oxides of Al and Cr. The Mo-x samples were subjected to prolonged oxidation (for 50 h) at 1000 °C in air. After 50 h of oxidation, the Mo-0 sample showed a weight gain of ∼24 mg/cm2 and remained intact. The energy dispersive spectroscopy analysis of the oxide scale formed after 50 h of oxidation revealed CrNbO4, Al2O3, and AlTiO5, which account for the enhanced oxidation resistance of Mo-0 and forecasts its potential for high-temperature applications. Submitted for publication in Journal of Alloys and Compounds

Ultra-rapid, physics-based development pathway for reactor-relevant RF antenna materials

2025-04-08T04:45:01Z

Ultra-rapid, physics-based development pathway for reactor-relevant RF antenna materials Wallace, Greg M.; Botica Artalejo, E.; Short, M.P.; Woller, K.B. This paper presents a rapid, atomistically-informed, experimental development pathway for fusion reactor-relevant radio frequency (RF) antenna materials in the Cu-Cr-(Nb,Al,Zr) composition system, with the goal of improving upon GRCop-84. RF antennas in a tokamak fusion reactor will face a unique set of challenges as both structural and functional materials. The desired material must simultaneously achieve and maintain high electrical conductivity, high strength, high thermal conductivity, resist high temperatures, possess low nuclear activation, and incur low damage due to neutron bombardment. The GRCop-84 alloy serves as a starting point for iterative improvement, with the desire to reduce or eliminate Nb from the material to minimize nuclear activation. The rapid development pathway makes use of a multi-target combinatorial thick film sputtering process to produce full ternary phase diagrams on a Si wafer substrate. Transient grating spectroscopy (TGS), a laser-ultrasonic method, will determine spatially-varying thermo-elastic properties, while four terminal electrical conductivity measurements will map out the best per- forming regions of the sample for in-depth study at larger length scales. High energy proton and self-ion irradiation emulates the effects of neutron damage on the thermal/electric properties. With rapid turnaround time (∼days) in terms of mapping radiation damage-induced material property changes in the full ternary system, these techniques allow rapid iteration towards an optimal material, testing hundreds of nearby compositions in the time it took to test one. Focused testing of larger, single composition samples (produced in an arc furnace or by laser sintering) provides data on structural and high power RF properties, and validates our thick-film based workflow. Submitted for publication in IEEE Transactions on Plasma Science

A 20-K, 600-W, Cryocooler-Based, Supercritical Helium Circulation System for the SPARC Toroidal Field Model Coil Program

2025-04-07T08:53:37Z

A 20-K, 600-W, Cryocooler-Based, Supercritical Helium Circulation System for the SPARC Toroidal Field Model Coil Program Michael, Philip C.; Golfinopoulos, Theodore; Ihloff, Ernest; Zhukovsky, Alexander; Schweiger, Shane; Fry, Vincent; O'Shea, Colin; Watterson, Amy; Nash, Daniel; Vieira, Rui F.; Doody, Jeffrey; Barnett, Raheem; Voirin, Erik A.; Bartoszek, Larry; Lations, Ricahrd F.; Hartwig, Zachary S. From June 2019 to July 2021, the MIT Plasma Science and Fusion Center in collaboration with Commonwealth Fusions Systems (CFS) designed, built, and commissioned a test facility at MIT to evaluate the performance of a REBCO-based, 2.9-m tall, 1.9-m wide Toroidal Field Model Coil (TFMC) for the SPARC tokamak. This paper presents the facility’s supercritical helium (SHe) circulation system design and measured performance. The facility employed a forced-flow SHe-circulation loop cooled by cryocoolers to provide a nominal cooling power of 600 W at 20 K and up to 70 g/s SHe flow to the TFMC at an absolute pressure of 20 bar. The reliance on cryocoolers as the facility’s cooling source was an ideal arrangement. Procurement costs were modest, acquisition time was reasonably, and siting requirements were minimal. Steady improvement in cryocooler design provided a simple to use system with sufficient cooling capacity for our needs. Extensive, closed-loop analyses were preformed both to support this procurement and to finalize the overall design of the SHe cooling circuit. The SHe system worked reliably, permitting flexible operation of the TFMC test facility at all working conditions. Submitted for publication in IEEE Transactions on Applied Superconductivity

A Cryogen-Free 25-T REBCO Magnet With the Extreme-No-Insulation Winding Technique

2025-04-07T09:06:13Z

A Cryogen-Free 25-T REBCO Magnet With the Extreme-No-Insulation Winding Technique Park, Dongkeun; Lee, Wooseung; Bascuñán, Juan; Kim, Ho Min; Iwasa, Yukikazu We present the operation result of a cryogen-free 23.5 T/ϕ12.5 mm-cold-boremagnet prototype composed of a stack of 12 no-insulation (NI) REBCO single pancake coils—ten middle coils of 6-mm wide and two end coils of 8-mm wide tape—forming 6 double pancake (DP) coils with inner joints. Each coil was wound with the tape having only 1-μm-thick copper layer on each side to overcome the conductor thickness uniformity issue and enhance the mechanical strength within the winding, and then, additional electrical shunting by thin layers of solder was applied on the top and bottom surfaces of eachDPcoil for effective cooling and quench protection—called extreme-NI winding technique.With this small prototypemagnet towards a benchtop 1-GHzNMR,wevalidate our coil design that include conductor performance, screening-currentinduced field and stresses, and conduction-cooling cryogenics. Included in the paper are: 1) conductor issues and our counterproposal in winding; 2) screening-current reduction method; 3) design and manufacture summary of the magnet; and 4) operating test results of the magnet up to 25 Tesla. Submitted for publication in IEEE Transactions on Applied Superconductivity

Design Overview of the MIT 1.3-GHz LTS/HTS NMR Magnet with a New REBCO Insert

2025-04-07T08:51:25Z

Design Overview of the MIT 1.3-GHz LTS/HTS NMR Magnet with a New REBCO Insert Park, Dongkeun; Bascunan, Juan; Li, Yi; Lee, Wooseung; Choi, Yoonhyuck; Iwasa, Yukikazu We present a design overview of the MIT 1.3-GHz LTS/HTS NMR magnet (1.3G) with a newly designed 835-MHz REBCO insert (H835) as a replacement for the 800-MHz REBCO insert (H800) that was damaged when it quenched during opera-tion in 2018. The new H835 is designed to contribute 19.6 T in a background field of 10.93 T by an LTS NMR magnet that normal-ly rated at 11.74 T (500 MHz): combined, 1.3G generates a total field of 30.53 T corresponding to a proton resonance frequency of 1.3 GHz. H835 is designed to operate stably while meeting 1.3G de-sign constraints. We have also designed H835 to protect it from permanent damage in an improbable event like a quench. Key de-sign features are: 1) a single-coil formation, composed of 38 stacked metal-co-wound no-insulation and 2 stacked no-insulation double-pancake coils, all with mechanically improved cross-over sections; 2) enhanced thermal stability; and 3) reduced current margin with a detect-and-heat method. This paper in-cludes: 1) electromagnetic and mechanical design of H835; 2) cryo-genics overview; 3) quench protection strategy; and 3) discussion on the next steps to successfully complete 1.3G. Submitted for publication in IEEE Transactions on Applied Superconductivity

3D xRAGE simulation of inertial confinement fusion implosion with imposed mode 2 laser drive asymmetry

2025-04-07T08:37:58Z

3D xRAGE simulation of inertial confinement fusion implosion with imposed mode 2 laser drive asymmetry Gatu Johnson, Maria; Haines, B.M.; Adrian, Patrick J.; Forrest, C.; Frenje, Johan A.; Glebov, V.Yu.; Grimble, W.; Janezic, R.; Knauer, J.P.; Lahmann, Brandon; Marshall, F.J.; Michel, T.; Séguin, Frederick H.; Stoeckl, C.; Petrasso, Richard D. Low-mode asymmetries represent an important obstacle to achieving high-gain inertial confinement fusion implosions. As a step in learning how to control such effects, an OMEGA experiment with imposed mode 2 laser drive asymmetries was done to study the expected signatures of this type of asymmetry [M. Gatu Johnson et al., PRE 2018]. In the present work, a 3D xRAGE simulation including the stalk mount has been brought to bear on the data from that experiment. Comprehensive comparisons between simulated and measured observables are made. Good agreement between simulated and measured x-ray image-inferred shell trajectories, bang times and neutron emission widths are seen, showing that the hydrodynamics are well captured in the simulation. Asymmetries seen in simulated and measured time-resolved and time-integrated x-ray images and areal densities also compare well, showing impact of both stalk and mode 2. On the other hand, important differences in measured and simulated neutron emission histories, yield, and ion temperature (Tion) asymmetries are seen, suggesting that the simulation is overestimating shock yield. The results clearly demonstrate the importance of considering all asymmetry sources when interpreting measured signatures of asymmetry. Submitted for publication in High Energy Density Physics

Progress Towards Interpretable Machine Learning-based Disruption Predictors Across Tokamaks

2025-04-08T04:23:08Z

Progress Towards Interpretable Machine Learning-based Disruption Predictors Across Tokamaks Rea, Christina; Mones, K.J.; Pau, A.; Granetz, R.S.; Sauter, O. In this paper we lay the groundwork for a robust cross-device comparison of data-driven disruption prediction algorithms on DIII-D and JET tokamaks. In order to consistently carry on a comparative analysis, we define physics-based indicators of disruption precursors based on temperature, density, and radiation profiles that are currently missing for DIII-D data. These profile-based indicators are shown to well-describe impurity accumulation events in both DIII-D and JET discharges that eventually disrupt. Thanks to the univariate analysis on the features used in such data-driven applications on both tokamaks, we are able to statistically highlight differences in the dominant disruption precursors: JET with its ITER-like wall is more prone to impurity accumulation events, while DIII-D is more subject to edge cooling mechanisms that destabilize dangerous MHD modes. Even though the analyzed datasets are characterized by such intrinsic differences, we show how data-driven algorithms trained on one device can be used to predict and interpret disruptive scenarios on the other. As long as the destabilizing precursors are diagnosed in a device-independent way, the knowledge that data-driven algorithms learn on one device can be used to explain a disruptive behavior on another device. Submitted for publication in Fusion Science and Technology

Drift kinetic theory of alpha transport by tokamak perturbations

2025-04-07T09:15:31Z

Drift kinetic theory of alpha transport by tokamak perturbations Tolman, Elizabeth A.; Catto, Peter J. Upcoming tokamak experiments fueled with deuterium and tritium are expected to have large alpha particle populations. Such experiments motivate new attention to the theory of alpha particle confinement and transport. A key topic is the interaction of alpha particles with perturbations to the tokamak fields, including those from magnetohydrodynamic modes like Alfvén eigenmodes and from ripple. These perturbations can transport alphas, leading to changed localization of alpha heating, loss of alpha power, and damage to device walls. Alpha interaction with these perturbations is often studied with single particle theory. In contrast, we derive a drift kinetic theory to calculate the alpha heat flux resulting from arbitrary perturbation frequency and periodicity (provided the frequency and periodicity can be studied drift kinetically). Novel features of the theory include the retention of a large effective collision frequency resulting from the resonant alpha collisional boundary layer, correlated interactions over many poloidal transits, and finite orbit effects. Heat fluxes are considered for the example cases of ripple and the toroidal Alfén eigenmode (TAE). The ripple heat flux is small. The TAE heat flux is significant and scales with the square of the perturbation amplitude, allowing the derivation of a constraint on mode amplitude for avoidance of significant alpha depletion. A simple saturation condition suggests that TAEs in one upcoming experiment will not cause significant alpha transport via the mechanisms in this theory. However, saturation above the level suggested by the simple condition, but within numerical and experimental experience, could cause significant transport. Submitted for publication in Journal of Plasma Physics

An ultrahigh-bandwidth Phase Contrast Imaging system for fusion plasmas

2025-04-08T04:20:27Z

An ultrahigh-bandwidth Phase Contrast Imaging system for fusion plasmas Marinoni, Alessandro; Rost, Jon C.; Porkolab, Miklos; Seraydarian, R. A novel Phase Contrast Imaging system that uses probing light in the near infrared region has been developed to image electron density fluctuations in fusion plasmas. As compared to standard systems operating in the mid infra-red region, the spectral response of the system is extended in wave-number and frequency response by 7 and 100 times, respectively. The internal structure of turbulence and radio-frequency waves is therefore accessible across an unprecedented wavelength and frequency range, extending into the electron gyro-radius scale and the GHz frequency region Submitted for publication in Journal of Instrumentation

Partial-Insulation HTS Magnet for Reduction of Quench-Induced Peak Currents

2025-04-08T04:21:41Z

Partial-Insulation HTS Magnet for Reduction of Quench-Induced Peak Currents Lee, Wooseung; Park, Dongkeun; Bascuñán, Juan; Iwasa, Yukikazu The No-insulation-like (NI) coil’s turn-to-turn current paths prevent local heating by forcing the current to bypass into nearby turns when a hot spot appears in a coil. However, the changing direction of the current by bypassing will change the magnetic flux, which generates unwanted induced currents in the adjacent coils in a multiply-stacked HTS magnet. This induced current can temporarily exceed the designed maximum currents in the NI coils, damaging the magnet. A partial-insulation (PI) coil, in which a single or multiple insulated, with a polyimide-like material or a thin ceramic film, is inserted between windings to hinder the current paths, can reduce the peak induced currents in theNIHTS coil’s current paths. In this paper, we present the results of a simulation study on the peak-induced current upon a quench of the PI HTS magnet with a double pancake. The study shows that the peak-induced current varies with the number of insulated turns.We also discuss the induced current turn-by-turn simulation. According to the simulation result, the PI effectively reduces overall induced current, especially insulation applied every two turns. Submitted for publication in IEEE Transactions on Applied Superconductivity

Design Overview of the MIT 1.3-GHz LTS/HTS NMR Magnet with a New REBCO Insert

2025-04-07T09:23:49Z

Design Overview of the MIT 1.3-GHz LTS/HTS NMR Magnet with a New REBCO Insert Park, Dongkeun; Bascuñán, Juan; Li, Yi; Lee, Wooseung; Choi, Yoonhyuck; Iwasa, Yukikazu We present a design overview of the MIT 1.3-GHz LTS/HTS NMR magnet (1.3G) with a newly designed 835-MHz REBCO insert (H835) as a replacement of the 800-MHz REBCO insert that was damaged when it quenched during operation in 2018. The new H835 contributes 19.6 T as designed, with an LTS back-ground magnet of 10.9 T, toward a total field of 30.5 T that corre-sponds to a proton resonance frequency of 1.3 GHz. The H835 is de-signed to be stable within 1.3G design constraints. The design also prevents the entire insert from permanent damage in the improba-ble event like a quench. Key design features are: 1) a single-solenoid structure, composed of 38 stacked metal-co-wound no-insula-tion and 4 stacked no-insulation double-pancake coils with mechan-ically improved cross-over sections; 2) enhanced thermal stability; and 3) reduced excessive current margin with a detect-and-activate-the-heater method. This paper includes: 1) electromagnetic and me-chanical design of the H835; 2) cryogenics overview; 3) quench pro-tection schemes; and 3) discussion on the next steps toward the 1.3G. Submitted for publication in IEEE Transactions on Applied Superconductivity

Characterization of MEMS Acoustic Sensors and Amplifiers in Cryogenic Fluids for Quench Detection Applications in HTS CICC

2025-04-07T08:36:18Z

Characterization of MEMS Acoustic Sensors and Amplifiers in Cryogenic Fluids for Quench Detection Applications in HTS CICC Zhoa, Z.; Moore, P.; Owen, C.; Anilus, M.; Chau, S.; Desai, A.; Emerling, M.; Chiesa, L.; Takayasu, Makoto; White, R. An acoustic quench detection method utilizing MEMS (Micro Electro-Mechanical System) acoustic sensors is proposed. To investigate this method, a commercially available MEMS pie-zoelectric microphone, the Vesper VM1000, and two types of second stage amplifiers, using either an OPA344 or a LMH6629 based amplifier circuit, were characterized at cryo-genic temperatures in helium gas. The MEMS microphones were in their original package with an integrated preamplifier. The tests were performed inside a two-stage Gifford-McMahon cryocooler from room temperature down to 60 K, at static pressures between 1.2 and 1.4 bar in gaseous helium, over the frequency band from 100 Hz to 10 kHz. Second stage amplifiers were needed to achieve signal to noise ratios approaching the manufacturer specified operating levels. The OPA344 based amplifier reduced in gain by >55 dB below 230 K, while the LMH6629 based amplifier performed well down to 60 K. The MEMS microphones appear to perform acoustic measure-ments down to 165 K but with some reduction in sensitivity down to 60 K. An acoustic model of the cryocooler plane wave tube calibration setup is developed and used to calibrate the microphone despite the presence of a significant thermal gradients down the plane wave tube. Submitted for publication in IEEE Transactions on Applied Superconductivity

Hot-Spot Modeling of REBCO NI Pancake Coil: Analytical and Experimental Approaches

2025-04-08T04:47:50Z

Hot-Spot Modeling of REBCO NI Pancake Coil: Analytical and Experimental Approaches Lee, Wooseung; Park, Dongkeun; Choi, Yoonhyuck; Li, Yi; Bascuana, Juan; Iwasa,Yukikazu The No-Insulation (NI)winding provides intrinsic bypassing current paths that enable self-protection fromoverheating. The self-protection of the NI coil is one of the most promising protection techniques for the high field high-temperature superconductor (HTS) magnet applications. Since the additional paths are valid for an HTS magnet with a thinner matrix, the self-protection mechanism is applicable even for the higher current density magnet with reduced matrix thickness inside the HTS tape. However, reducing the matrix can cause damage to the magnet by producing excessive heat during the quench. This research introduces a new modeling method to investigate the hot-spot characteristics in the REBCO NI pancake coil. Themodel is also validated with a sample NI HTS coil experiment result. Radial direction Normal Zone Propagation (NZP) velocity of the sample coil is estimated based on the suggested model. The calculated radial direction NZP velocity is applied to calculate the center field drop of the NI HTS coil, and the result is well-matched with the experiment result.We also introduce one example of the model applications. The maximum current density that will not exceed a given reference temperature in the adiabatic cooling condition is estimated using the model. Submitted for publication in IEEE Transactions on Applied Superconductivity

A more flexible design for MDSplus Device drivers

2025-04-08T04:23:56Z

A more flexible design for MDSplus Device drivers Santoro, Fernando; Lane-Walsh, Stephen; Stiller, Joshua; Winkel, Mark The traditional approach to building MDSplus Device drivers is rigid and lacks the ability to meet changing needs. We introduce a novel paradigm for Device driver development that allows the tree structure to dynamically change. This allows device drivers that can reconfigure to automatically reflect the hardware it represents, or a device that implements a variable number of queries to an external database. We have created a driver using this paradigm that communicates with a digitizer, queries the modules attached, and builds a MDSplus tree structure to utilize them. Additionally, this driver can reconfigure to match changes in the digitizer, by adding or deleting nodes using overwrite and/or delete modes. We also wrote a method for verifying both the setting provided and that the hardware matches the last known state. We have added fields to help validate settings such as min/max limits, and a list of allowed values. The definitions of the nodes which make of the device have been augmented to include help, tool tips and validation ranges. This will facilitate automated user interface generation. Submitted for publication in Fusion Engineering and Design

Introduction to MDSplus using Docker

2025-04-08T04:43:03Z

Introduction to MDSplus using Docker Lane-Walsh, Stephen; Stillerman, J.; Santoro, Fernando; Fredian, T. With increased use of MDSplus1 comes an influx of new users. With them comes a need for more and better ways to learn the suite of tools that is MDSplus. The MDSplus team continually evaluates new technologies to improve our software and user experience. To this end, we investigated Docker to determine if and how it could help new users understand MDSplus, make MDSplus easier to install, and allow us to easily test old/new versions. To achieve this, a set of Docker images and instructions have been developed. This paper will provide an overview of MDSplus, and detail the methods to create and use the Docker images. Additionally, we will explore the limitations of such an approach, and the recommended applications.The project where these Docker Images were built, along with the Demo is here: https://github.com/WhoBrokeTheBuild/DockerizedMDSplus https://hub.docker.com/r/whobrokethebuild/mdsplus The now official Docker Images are available here: https://github.com/MDSplus/Docker https://hub.docker.com/r/mdsplus/mdsplus Submitted for publication in Fusion Engineering and Design

Fusion Plasma Turbulence Research Beyond the Burning Plasma Era: Perspectives on Transport Model Validation in Fusion and Fission

2025-04-07T08:31:45Z

Fusion Plasma Turbulence Research Beyond the Burning Plasma Era: Perspectives on Transport Model Validation in Fusion and Fission White, Anne E.; Baglietto, E.; Bucci, M.; Howard, Nathan T.; Rodriguez Fernandez, Pablo In fusion, the validation of turbulent transport models is undertaken with the goals of making basic physics discoveries as well as for development of new predictive models to improve the operation and enhance the performance of existing and future fusion reactors. A fusion industry is just beginning to emerge globally. Like fission, validation in fusion energy research is a vibrant research area, but unlike fusion, a fission industry exists. The fission power industry motivates validation efforts, often performed at universities with small-scale experiments and advanced models and simulations developed in-house. Because fission research spans basic physics and applications, and addresses near-term and long-term industry interests, validation is thriving. This perspective article describes the validation of turbulent transport models in both fusion research and fission research, draws parallels between the validation methods and techniques used in two areas of the fields, and presents an outlook for thriving university fusion and fission research programs underpinned by a virtual cycle of basic and applied research that supports industry needs as well as tackling intellectual grand challenges. Submitted for publication in Frontiers in Nuclear Engineering

On the future sustainable ultra-high-speed maglev: An energy-economical superconducting linear thrusting system

2025-04-07T08:34:19Z

On the future sustainable ultra-high-speed maglev: An energy-economical superconducting linear thrusting system Dong, Fangliang; Hao, Luning; Park, Dongkeun; Iwasa, Yukikazu; Huang, Zhen Along with 1000-km/h magnetically levitated trains (maglevs), an era of future traveling is approaching. With only ∼1/5 energy consumption per passenger kilometer while achieving a similar speed compared to airplanes, the ultra-high-speed maglevs would change the way the world moves with an on-demand sustainable mass transportation system that connects cities in minutes. Meanwhile, with ever-advancing superconducting technology, the zero-joule-loss magnet in high-density-energy preservation is much improved with strong magnetic field. This consequently enables the energy-efficient but powerful superconducting linear thrusting system - the key part that drives the maglevs to the speed, in an even more energy-friendly way. Here, we take advantage of superconductor, and present successful solutions to two energy bottlenecks regarding energy preservation and conversion unique to this novel thrusting system, that is, 1) on-board feeding power constraint and 2) field-ripple-caused loss, by demonstrating a prototype with two merits: 1) its on-board superconducting propulsive magnet can operate as a standalone system free of any on-board feeding powers for maintaining energizing and cryogenic cooling; 2) the ground propulsive structure can greatly suppress thermal loss during operation. We hope the work could solve energy issues in the future maglev, and prompt the process of transport electrification and decarbonization. Submitted for publication in Energy Conversion and Management

Effects of neutral particles on edge dynamics in Alcator C-Mod plasmas

2019-04-11T02:56:38Z

Effects of neutral particles on edge dynamics in Alcator C-Mod plasmas Boivin, R.L.; Goetz, J.A.; Hubbard, A.E.; Hughes, J.W.; Hutchinson, I.H.; Irby, J.H.; Bombard, B.; Marmar, E.S.; Mossessian, D.; Pitcher, C.S.; Terry, J.L.; Carreras, B.A.; Owen, L.W.

Studies of EDA H-Mode in Alcator C-Mod

2019-04-11T02:56:38Z

Studies of EDA H-Mode in Alcator C-Mod Greenwald, M.; Boivin, R.; Bonoli, P.; Fiore, C.; Goetz, J.; Granetz, R.; Hubbard, A.; Hutchinson, I.; Irby, J.; Lin, Y.; Marmar, E.; Mazurenko, A.; Mossessian, D.; Pedersen, T.; Rice, J.; Snipes, J.; Schilling, G.; Taylor, G.; Terry, J.; Wolfe, S.; Wukitch, S.

Physics and Scaling of the H-mode Pedestal

2019-04-11T02:56:43Z

Physics and Scaling of the H-mode Pedestal Hubbard, A.E.

Convective cell formation in a levitated dipole

2019-04-10T20:04:53Z

Convective cell formation in a levitated dipole Kesner, J.; Garnier, D.T.

Observation of Self Absorption of Mercury I and Cadmium I Emission in an Atmospheric Microwave Sustained Plasma

2019-04-11T02:56:37Z

Observation of Self Absorption of Mercury I and Cadmium I Emission in an Atmospheric Microwave Sustained Plasma Hadidi, K.; Woskov, P.; Green, K.; Thomas, P.

Impurity toroidal rotation and transport in Alcator C-Mod ohmic h-mode plasmas

2019-04-09T15:40:40Z

Impurity toroidal rotation and transport in Alcator C-Mod ohmic h-mode plasmas Rice, J.E.; Goetz, J.A.; Granetz, R.S.; Greenwald, M.J.; Hubbard, A.E.; Hutchinson, I.H.; Marmar, E.S.; Mossessian, D.; Pedersen, T.; Snipes, J.A.; Terry, J.L.; Wolfe, S.M.

A Shaped-Foil Recoil Spectrometer for Neutron Time-of-Flight Measurements

2019-04-11T02:55:53Z

A Shaped-Foil Recoil Spectrometer for Neutron Time-of-Flight Measurements Li, C.K.; Seguin, F.H.; Petrasso, R.D.; Sangster, T.C.

Matched Filtering for the Measurement of Ducted VLF Emissions

2019-04-12T20:34:04Z

Matched Filtering for the Measurement of Ducted VLF Emissions Starks, M.J.; Lee, M.C.

Design of Correcting Mirrors for a Gyrotron Used at Large Helical Device

2019-04-12T20:34:21Z

Design of Correcting Mirrors for a Gyrotron Used at Large Helical Device Shapiro, M.A.; Chu, T.S.; Denison, D.R.; Sato, M.; Shimozuma, T.; Temkin, R.J.

Decorrelation of Edge Plasma Turbulence at the Transition from Low- to High-Confinement Mode in the DIII-D Tokamak

2019-04-12T20:34:21Z

Decorrelation of Edge Plasma Turbulence at the Transition from Low- to High-Confinement Mode in the DIII-D Tokamak Coda, S.; Porkolab, M.; Burrell, K.H.

Studies of MeV Fast Protons Produced in Laser Fusion Experiments

2019-04-12T20:34:05Z

Studies of MeV Fast Protons Produced in Laser Fusion Experiments Hicks, D.G.; Li, C.K.; Seguin, F.H.; Ram, A.K.; Petrasso, R.D.; Soures, J.M.; Meyerhofer, D.D.; Roberts, S.; Schnittman, J.D.; Sorce, C.; Stockl, C.; Sangster, T.C.; Phillips, T.W.

Combined RF Current Drive and Bootstrap Current in Tokamaks

2019-04-11T02:55:47Z

Combined RF Current Drive and Bootstrap Current in Tokamaks Schultz, S.D.; Bers, A.; Ram, A.K.

D-3He Proton Spectra for Diagnosing Shell r R and Fuel Ti of Imploded Capsules at OMEGA

2019-04-11T02:55:52Z

D-3He Proton Spectra for Diagnosing Shell r R and Fuel Ti of Imploded Capsules at OMEGA Li, C.K.; Hicks, D.G.; Seguin, F.H.; Petrasso, R.D.; Soures, J.M.; Radha, P.B.; Glebov, V.; Stoeckl, C.; Knauer, J.P.; Kremens, R.; Marshall, F.J.; Meyerhofer, D.D.; Skupsky, S.; Roberts, S.; Sorce, C.; Sangster, T.C.; Phillips, T.W.; Cab, M.D.

ICRF Heating in Alcator C-Mod: Present Status and Future Prospects

2019-04-09T16:30:21Z

ICRF Heating in Alcator C-Mod: Present Status and Future Prospects Porkolab, M.; Fiore, C.; Greenwald, M.; Hosea, J.C.; Hubbard, A.; Hutchinson, I.; Irby, J.; Melby, E.; Marmar, E.; Phillips, C.K.; Reardon, J.; Rice, J.; Schilling, G.; Terry, J.; Wolfe, S.; Wukitch, S.; Wilson, J.R.

Note on Group Velocity and Energy Propagation

2019-04-12T20:34:04Z

Note on Group Velocity and Energy Propagation Bers, Abraham

The Rydberg Series of Heliumlike Cl, Ar and S and Their High n Satellites in Tokamak Plasmas

2019-04-12T20:34:04Z

The Rydberg Series of Heliumlike Cl, Ar and S and Their High n Satellites in Tokamak Plasmas Rice, J.E.; Fournier, K.B.; Safronova, U.I.; Goetz, J.A.; Gutmann, S.; Hubbard, A.E.; Irby, J.; Bombard, B.; Marmar, E.S.; Terry, J.

Electron Bernstein Wave Excitation in NSTX-Type High-ß Plasmas

2019-04-12T20:34:02Z

Electron Bernstein Wave Excitation in NSTX-Type High-ß Plasmas Ram, Abhay

Options for the Use of High Temperature Superconductor in Tokamak Fusion Reactor Designs

2019-04-10T13:17:46Z

Options for the Use of High Temperature Superconductor in Tokamak Fusion Reactor Designs Bromberg, L.; Tekula, M.

Magnetohydrodynamic Stability in a Levitated Dipole

2019-04-10T13:17:46Z

Magnetohydrodynamic Stability in a Levitated Dipole Garnier, D.; Kesner, J.; Mauel, M.

Plasma Rotation during Ohmic H-modes in the Alcator C-Mod Tokamak

2019-04-10T13:17:46Z

Plasma Rotation during Ohmic H-modes in the Alcator C-Mod Tokamak Hutchinson, I.H.; Rice, J.E.; Granetz, R.S.; Snipes, J.A.

Plasma Catalytic Reforming of Natural Gas

2019-04-09T17:44:58Z

Plasma Catalytic Reforming of Natural Gas Bromberg, L.; Rabinovich, A.; Alexeev, N.; Cohn, D.R.

System optimization and cost analysis of plasma catalytic reforming of hydrocarbons

2019-04-10T13:17:47Z

System optimization and cost analysis of plasma catalytic reforming of hydrocarbons Bromberg, L.; Cohn, D.R.; Rabinovich, A.; Alexeev, N.; Samokhin, A.; Ramprasad, R.; Tamhankar, S.

Molybdenum sources and transport in the Alcator C-Mod tokamak

2019-04-12T20:48:58Z

Molybdenum sources and transport in the Alcator C-Mod tokamak Pappas, D.A.; Lipschultz, B.; Bombard, B.; May, M.J.; Pitcher, C.S.

Accurate and Sensitive Metals Emissions Monitoring with an Atmospheric Microwave Plasma having a Real-Time Span Calibration

2019-04-10T20:04:44Z

Accurate and Sensitive Metals Emissions Monitoring with an Atmospheric Microwave Plasma having a Real-Time Span Calibration Woskov, Paul; Hadidi, Kamal; Thomas, Paul; Green, Karyn; Flores, Guadalupe

Whistler Wave Interactions with Space Plasmas during HF Heating of the Ionosphere at Arecibo

2019-04-12T20:48:59Z

Whistler Wave Interactions with Space Plasmas during HF Heating of the Ionosphere at Arecibo Lee, M.C.; Starks, M.J.; Burke, W.J.; Kuo, S.P.; Sulzer, M.P.; Riddolls, R.J.; Zhang, A.X.

Mode-converted electron Bernstein waves for heating and current drive in NSTX

2019-04-10T13:17:43Z

Mode-converted electron Bernstein waves for heating and current drive in NSTX Schultz, S.D.; Ram, A.K.; Bers, A.

Central Impurity Toroidal Rotation in ICRF Heated Alcator C-Mod Plasmas

2019-04-10T13:17:45Z

Central Impurity Toroidal Rotation in ICRF Heated Alcator C-Mod Plasmas Rice, J.E.; Bonoli, P.T.; Goetz, J.A.; Greenwald, M.J.; Hutchinson, I.H.; Marmar, E.S.; Wolfe, S.M.; Wukitch, S.; Chang, C.S.

Acceleration of Ionospheric Ions by Wave-Particle Interactions

2019-04-10T13:17:45Z

Acceleration of Ionospheric Ions by Wave-Particle Interactions Ram, Abhay

Effect of Oxygen Concentration on the Detection of Mercury in an Atmospheric Microwave Discharge

2019-04-10T13:17:42Z

Effect of Oxygen Concentration on the Detection of Mercury in an Atmospheric Microwave Discharge Hadidi, K.; Woskov, P.P.; Flores, G.J.; Green, K.; Thomas, P.

Plasma Reforming of Diesel Fuel

2019-04-12T20:48:58Z

Plasma Reforming of Diesel Fuel Bromberg, L.; Rabinovich, A.; Alexeev, N.; Cohn, D.R.

Efficient, Modular Microwave Plasma Torch for Thermal Treatment

2019-04-12T20:48:58Z

Efficient, Modular Microwave Plasma Torch for Thermal Treatment Hadidi, K.; Woskov, P.P.

The role of particle sinks and sources in Alcator C-Mod detached divertor discharges

2019-04-10T20:18:52Z

The role of particle sinks and sources in Alcator C-Mod detached divertor discharges Lipschultz, B.; Terry, J.L.; Boswell, C.; Goetz, J.A.; Hubbard, A.E.; Krasheninnikov, S.I.; Bombard, B.; Pappas, D.A.; Pitcher, C.S.; Wising, F.; Wukitch, S.

Advanced Tokamak Burning Plasma Experiment

2019-04-10T13:17:41Z

Advanced Tokamak Burning Plasma Experiment Porkolab, M.; Bonoli, P.T.; Ramos, J.; Schultz, J.; Nevins, W.N.

Gyrotron Internal Mode Converter Reflector Shaping from Measured Field Intensity

2019-04-10T13:17:42Z

Gyrotron Internal Mode Converter Reflector Shaping from Measured Field Intensity Denison, D.R.; Chu, T.S.; Shapiro, M.A.; Temkin, R.J.

Electromagnetic Analysis and Cold Test of a Distributed Window for a High Power Gyrotron

2019-04-10T13:17:42Z

Electromagnetic Analysis and Cold Test of a Distributed Window for a High Power Gyrotron Shapiro, M.A.; Moeller, C.P.; Temkin, R.J.

Modeling of particle and energy transport in the edge plasma of Alcator C-Mod

2019-04-09T15:40:01Z

Modeling of particle and energy transport in the edge plasma of Alcator C-Mod Umansky, M.V.; Krasheninnikov, S.I.; Bombard, B.; Lipschultz, B.; Terry, J.L.

High Confinement Dissipative Divertor Operation on Alcator C-Mod

2019-04-12T20:48:57Z

High Confinement Dissipative Divertor Operation on Alcator C-Mod Goetz, J.A.; Bombard, B.; Lipschultz, B.; Pitcher, C.S.; Terry, J.L.; Boswell, C.; Gangadhara, S.; Pappas, D.; Weaver, J.; Welch, B.; Boivin, R.L.; Bonoli, P.; Fiore, C.; Granetz, R.; Greenwald, M.; Hubbard, A.; Hutchinson, I.; Irby, J.; Marmar, E.; Mosses, D.

Phase Space Structure for Intense Charged-Particle Beams in Periodic Focusing Transport Systems

2019-04-10T13:17:40Z

Phase Space Structure for Intense Charged-Particle Beams in Periodic Focusing Transport Systems Chen, C.; Pakter, R.; Davidson, R.C.

Transport in Alcator C-Mod H-Modes

2019-04-09T18:46:47Z

Transport in Alcator C-Mod H-Modes Greenwald, M.; Boivin, R.; Bonoli, P.; Budny, R.; Fiore, C.; Goetz, J.; Granetz, R.; Hubbard, A.; Hutchinson, I.; Irby, J.; Bombard, B.; Lin, Y.; Lipschultz, B.; Marmar, E.; Mazurenko, A.; Mossessian, D.; Pitcher, C.S.; Porkolab, M.; Rice, J.; Rowan, W.; Snipes, J.

A comparison between two adaptive numerical methods for edge plasma fluid modeling

2019-04-10T13:17:41Z

A comparison between two adaptive numerical methods for edge plasma fluid modeling Subba, F.; Batishchev, O.V.; Zanino, R.

Detached Divertor Plasmas In Alcator C-Mod: A Study Of The Role Of Atomic Physics

2019-04-11T02:55:17Z

Detached Divertor Plasmas In Alcator C-Mod: A Study Of The Role Of Atomic Physics Lipschultz, B.; Boswell, C.; Goetz, J.A.; Pitcher, C.S.; Terry, J.L.; Weaver, J.L.; Welch, B.L.; Hubbard, A.; Krasheninnikov, S.I.; Labombard, B.L.; Pappas, D.A.

Real-time calibrated microwave plasma multimetals emissions monitor

2019-04-12T20:48:57Z

Real-time calibrated microwave plasma multimetals emissions monitor Woskov, Paul; Hadidi, Kamal; Thomas, Paul; Green, Karyn; Flores, Guadalupe

Recombination & ion loss in C-Mod detached divertor discharges

2019-04-12T20:48:57Z

Recombination & ion loss in C-Mod detached divertor discharges Lipschultz, B.; Terry, J.L.; Boswell, C.; Krasheninnikov, S.I.; Bombard, B.; Pappas, D.A.

Upgrade of Reflectometry Profile and Fluctuation Measurements in Alcator C-Mod

2019-04-12T20:48:55Z

Upgrade of Reflectometry Profile and Fluctuation Measurements in Alcator C-Mod Lin, Y.; Irby, J.; Stek, P.; Hutchinson, I.; Snipes, J.; Nazikian, R.; Carthy, M.

H-Mode regimes and observations of central toroidal rotation in Alcator C-Mod

2019-04-12T20:48:56Z

H-Mode regimes and observations of central toroidal rotation in Alcator C-Mod Greenwald, M.; Rice, J.; Boivin, R.; Bonoli, P.; Budny, R.; Chang, C.S.; Ernst, D.; Fiore, C.; Goetz, J.; Granetz, R.; Hubbard, A.; Hutchinson, I.; Irby, J.; Bombard, B.; Lipschultz, B.; Marmar, E.; Mossessian, D.; Porkolab, M.; Rowan, W.; Snipes, J.; Schilling, G.; Tak, Y.

Spectroscopic Diagnostics of an Atmospheric Microwave Plasma for Monitoring Metals Pollution

2019-04-10T13:17:39Z

Spectroscopic Diagnostics of an Atmospheric Microwave Plasma for Monitoring Metals Pollution Woskov, P.P.; Hadidi, K.; Borras, M.C.; Thomas, P.; Green, K.; Flores, G.J.

Study of Volume Recombination and Radiation Opacity Effects in Alcator C-Mod

2019-04-12T20:48:55Z

Study of Volume Recombination and Radiation Opacity Effects in Alcator C-Mod Terry, J.L.; Lipschultz, B.; Pigarov, A.; Boswell, C.; Krasheninnikov, S.I.; Bombard, B.; Pappas, D.A.

On the experimental determination of the volume recombination rate in tokamak divertors

2019-04-09T17:18:59Z

On the experimental determination of the volume recombination rate in tokamak divertors Terry, J.L.; Lipschultz, B.; Bonnin, X.; Boswell, C.; Krasheninnikov, S.I.; Pigarov, A.; Bombard, B.; Pappas, D.A.; Scott, H.A.

Performance of Alcator C-Mod Core Thomson Scattering System

2019-04-10T19:48:11Z

Performance of Alcator C-Mod Core Thomson Scattering System Mossessian, D.A.; Hubbard, A.; Irby, J.

Halo Formation in Intense Linacs

2019-04-12T20:48:55Z

Halo Formation in Intense Linacs Chen, C.

Kiloampere and Microsecond Electron Beams from Ferroelectric Cathodes

2019-04-10T13:17:38Z

Kiloampere and Microsecond Electron Beams from Ferroelectric Cathodes Advani, R.N.; Hogge, J.P.; Kreischer, K.; Mulligan, W.; Temkin, R.; Kirkman, G.F.; Jiang, B.; Reinhardt, N.

Neutral particle and radiation effects on Pfirsch-Schuter fluxes near the edge

2019-04-10T13:17:38Z

Neutral particle and radiation effects on Pfirsch-Schuter fluxes near the edge Catto, P.J.; Helander, P.; Connor, J.W.; Hazeltine, R.

High resolution bolometry on the Alcator C-Mod tokamak

2019-04-10T13:17:39Z

High resolution bolometry on the Alcator C-Mod tokamak Boivin, R.L.; Goetz, J.A.; Marmar, E.S.; Terry, J.L.

Unstructured adaptive grid and gridfree methods for edge plasmas fluid simulations

2019-04-12T20:48:54Z

Unstructured adaptive grid and gridfree methods for edge plasmas fluid simulations Batishchev, O.V.; Batishcheva, A.A.; Kholodov, A.S.; Krasheninnikov, S.I.; Sigmar, D.J.

Impurity compression and enrichment studies on Alcator C-Mod

2019-04-12T20:48:54Z

Impurity compression and enrichment studies on Alcator C-Mod Goetz, J.A.; Lipschultz, B.; Pitcher, C.S.; Terry, J.L.; Bonoli, P.T.; Rice, J.E.; Wukitch, S.J.

A novel tracer-gas injection system for scrape-off layer impurity transport and screening experiments

2019-04-10T13:17:24Z

A novel tracer-gas injection system for scrape-off layer impurity transport and screening experiments Bombard, B.; Gangadhara, S.; Lipschultz, B.; Lisgo, S.; Pappas, D.A.; Pitcher, C.S.; Stangeby, P.; Terry, J.

Electron cyclotron discharge cleaning experiments on Alcator C-Mod

2019-04-10T13:17:24Z

Electron cyclotron discharge cleaning experiments on Alcator C-Mod Nachtrieb, R.T.; Bombard, B.L.; Terry, J.L.; Reardon, J.C.; Rowan, W.L.; Wampler, W.R.

The role of friction in SOL pressure balance in Alcator C-Mod

2019-04-12T20:48:48Z

The role of friction in SOL pressure balance in Alcator C-Mod Pitcher, C.S.; Goetz, J.A.; Bombard, B.; Lipschultz, B.; Weaver, J.L.; Welch, B.L.

Recent progress in ICRF physics

2019-04-09T17:15:44Z

Recent progress in ICRF physics Porkolab, Miklos; Becoulet, A.; Bonoli, P.T.; Gormezano, C.; Koch, R.; Majeski, R.J.; Messiaen, A.; Noterdaeme, J.M.; Petty, C.; Pinsker, R.; Start, D.; Wilson, R.

Experimental and theoretical investigations of a 17 GHz RF gun

2019-04-10T13:17:22Z

Experimental and theoretical investigations of a 17 GHz RF gun Brown, W.J.; Trotz, S.; Kreischer, K.E.; Pedrozzi, M.; Shapiro, M.A.; Temkin, R.J.

A coupling between cross-field density and temperature gradient scale lengths in high-recycling scrape-off layers

2019-04-12T20:30:44Z

A coupling between cross-field density and temperature gradient scale lengths in high-recycling scrape-off layers Bombard, B.

Neutral diffusion and anomalous effects of ion flow shear

2019-04-09T15:25:17Z

Neutral diffusion and anomalous effects of ion flow shear Fulop, T.; Catto, P.J.; Helander, P.

Intensity effects on inverse-Bremsstrahlung electron acceleration

2019-04-12T20:48:44Z

Intensity effects on inverse-Bremsstrahlung electron acceleration Pakter, R.

Coupling to Electron Bernstein Waves in Tokamaks

2019-04-12T20:48:44Z

Coupling to Electron Bernstein Waves in Tokamaks Bers, A.; Ram, A.K.; Schultz, S.D.

Interaction of ions with a spectrum of electrostatic waves

2019-04-12T20:48:44Z

Interaction of ions with a spectrum of electrostatic waves Ram, A.K.; Bers, A.; Benisti, D.

Comments on particle and energy balance in the edge plasma of Alcator C-Mod

2019-04-12T20:48:47Z

Comments on particle and energy balance in the edge plasma of Alcator C-Mod Umansky, M.V.; Krasheninnikov, S.I.; Bombard, B.; Terry, J.L.

Ultra-high densities and volume recombination inside the separatrix of the Alcator C-Mod tokamak

2019-04-12T20:48:47Z

Ultra-high densities and volume recombination inside the separatrix of the Alcator C-Mod tokamak Lipschultz, B.; Terry, J.L.; Boswell, C.; Hubbard, A.; Bombard, B.; Pappas, D.A.

Stability of a plasma confined in a Dipole Field

2019-04-10T13:17:20Z

Stability of a plasma confined in a Dipole Field Kesner, J.

New mechanisms of ion energization by multiple electrostatic waves in a magnetized plasma

2019-04-12T20:48:41Z

New mechanisms of ion energization by multiple electrostatic waves in a magnetized plasma Benisti, D.; Ram, A.K.; Bers, A.

Ion dynamics in multiple electrostatic waves in a magnetized plasma -- Part II: Enhancement of the acceleration

2019-04-12T20:48:43Z

Ion dynamics in multiple electrostatic waves in a magnetized plasma -- Part II: Enhancement of the acceleration Benisti, D.; Ram, A.K.; Bers, A.

Ion dynamics in multiple electrostatic waves in a magnetized plasma -- Part I: Coherent acceleration

2019-04-12T20:48:42Z

Ion dynamics in multiple electrostatic waves in a magnetized plasma -- Part I: Coherent acceleration Benisti, D.; Ram, A.K.; Bers, A.

ELMs and fast edge fluctuations in Alcator C-Mod

2019-04-10T13:17:18Z

ELMs and fast edge fluctuations in Alcator C-Mod Snipes, J.A.; Granetz, R.S.; Greenwald, M.; Hubbard, A.E.; Irby, J.; Kesner, J.; Migliuolo, S.; Pedersen, T.S.; Ramos, J.; Rice, J.; Stek, P.C.; Takase, Y.; Wolfe, S.M.

Volume recombination and opacity in Alcator C-Mod divertor plasmas

2019-04-10T13:17:18Z

Volume recombination and opacity in Alcator C-Mod divertor plasmas Terry, J.L.; Lipschultz, B.; Pigarov, A.; Krasheninnikov, S.I.; Bombard, B.; Lumma, D.; Ohkawa, H.; Pappas, D.; Umansky, M.

Study of the discrete-to-continuum transition in a Balmer spectrum from Alcator C-Mod divertor plasmas

2019-04-10T13:17:19Z

Study of the discrete-to-continuum transition in a Balmer spectrum from Alcator C-Mod divertor plasmas Pigarov, A.Y.; Terry, J.L.; Lipschultz, B.

Stability properties of coherently gyrating relativistic electron beams

2019-04-12T20:48:40Z

Stability properties of coherently gyrating relativistic electron beams Davies, J.A.; Chen, C.

140 GHz gyrotron experiments based on a confocal cavity

2019-04-09T19:01:05Z

140 GHz gyrotron experiments based on a confocal cavity Hu, W.; Shapiro, M.A.; Kreischer, K.E.; Temkin, R.J.

Measurements of the H-mode pedestal region on Alcator C-Mod

2019-04-12T20:48:41Z

Measurements of the H-mode pedestal region on Alcator C-Mod Hubbard, A.E.; Boivin, R.L.; Granetz, R.S.; Greenwald, M.; Hutchinson, I.H.; Irby, J.H.; In, J.; Kesner, B.; Labombard, B.; Lin, Y.; Rice, J.E.; Pedersen, T.S.; Snipes, J.A.; Stek, P.C.; Takase, Y.; Wolfe, S.M.; Wukitch, S.

Transport Phenomena in Alcator C-Mod H-Modes

2019-04-10T13:17:17Z

Transport Phenomena in Alcator C-Mod H-Modes Greenwald, M.; Schachter, J.; Dorland, W.; Granetz, R.; Hubbard, A.; Rice, J.; Snipes, J.A.; Stek, P.; Wolfe, S.

MDSplus remote collaboration support -- internet and World Wide Web

2019-04-10T13:17:14Z

MDSplus remote collaboration support -- internet and World Wide Web Fredian, T.W.; Stillerman, J.A.

Ionospheric ion acceleration by multiple electrostatic waves

2019-04-10T13:17:17Z

Ionospheric ion acceleration by multiple electrostatic waves Ram, A.K.; Bers, A.; Benisti, D.

Ion Dynamics in Multiple Electrostatic Waves in a Magnetized Plasma

2019-04-10T13:17:18Z

Ion Dynamics in Multiple Electrostatic Waves in a Magnetized Plasma Benisti, D.; Ram, A.K.; Bers, A.

Local variables affecting H-mode threshold on Alcator C-Mod

2019-04-11T03:51:36Z

Local variables affecting H-mode threshold on Alcator C-Mod Hubbard, A.E.; Boivin, R.L.; Drake, J.F.; Greenwald, M.; In, Y.; Irby, J.H.; Rogers, B.N.; Snipes, J.A.

The MDSplus data acquisition system, current status and future directions

2019-04-12T20:48:17Z

The MDSplus data acquisition system, current status and future directions Stillerman, J.A.; Fredian, T.W.

Papers presented at the 24th EPS conference on controlled fusion and plasma physics by the Alcator C-Mod group (Berchtesgaden, Germany, 9-13 June 1997)

2019-04-12T20:48:16Z

Papers presented at the 24th EPS conference on controlled fusion and plasma physics by the Alcator C-Mod group (Berchtesgaden, Germany, 9-13 June 1997)

Edge emittance growth and particle diffusion induced by discrete-particle effects in intense beam simulations

2019-04-09T16:41:48Z

Edge emittance growth and particle diffusion induced by discrete-particle effects in intense beam simulations Pakter, R.; Chen, C.

The measurement of the instrinsic impurities of molybdenum and carbon in the Alcator C-Mod tokamak plasma using low resolution spectroscopy

2019-04-09T17:10:23Z

The measurement of the instrinsic impurities of molybdenum and carbon in the Alcator C-Mod tokamak plasma using low resolution spectroscopy May, M.J.; Finkenthal, M.; Regan, S.P.; Moos, H.W.; Terry, J.L.; Goetz, J.A.; Graf, M.A.; Rice, J.E.; Marmar, E.S.; Fournier, K.B.; Goldston, W.H.

RF effects on neoclassical theory and the bootstrap current in tokamaks

2019-04-10T23:14:55Z

RF effects on neoclassical theory and the bootstrap current in tokamaks Schultz, S.D.; Bers, A.; Ram, A.K.

Mode conversion to ion-Bernstein waves of fast Alfven waves with poloidal wavenumbers in sheared magnetic fields

2019-04-12T20:48:15Z

Mode conversion to ion-Bernstein waves of fast Alfven waves with poloidal wavenumbers in sheared magnetic fields Schultz, S.D.; Bers, A.; Ram, A.K.

Electron cyclotron heating in NSTX

2019-04-12T20:48:15Z

Electron cyclotron heating in NSTX Wu, K.C.; Ram, A.K.; Bers, A.; Schultz, S.D.

Plasma confinement in a levitated magnetic dipole

2019-04-09T18:22:00Z

Plasma confinement in a levitated magnetic dipole Kesner, J.; Mauel, M.

Theoretical analysis of mode conversion electron heating experiments in Alcator C-Mod

2019-04-12T20:48:16Z

Theoretical analysis of mode conversion electron heating experiments in Alcator C-Mod Bonoli, P.T.; Shea, P.J.; Brambilla, M.; Hubbard, A.; Porkolab, M.; Takase, Y.; Wukitch, S.

ICRF-heated enhancement confinement modes in the Alcator C-Mod tokamak

2019-04-10T23:14:51Z

ICRF-heated enhancement confinement modes in the Alcator C-Mod tokamak Takase, Y.; Boivin, R.L.; Bombarda, F.; Bonoli, P.; Christensen, C.; Fiore, C.; Garnier, D.; Goetz, J.; Golovato, S.; Granetz, R.; Greenwald, M.; Horne, S.; Hubbard, A.; Hutchinson, I.; Irby, J.; Bombard, B.; Lipshultz, B.; Marmar, E.; May, M.

Impurity transport in Alcator C-Mod plasmas

2019-04-10T23:14:51Z

Impurity transport in Alcator C-Mod plasmas Rice, J.E.; Terry, J.L.; Goetz, J.A.; Wang, Y.; Marmar, E.S.; Greenwald, M.; Hutchinson, I.H.; Takase, Y.; Wolfe, S.; Ohkawa, H.; Hubbard, A.

High power operation of a 17 GHz photocathode RF gun

2019-04-10T23:14:51Z

High power operation of a 17 GHz photocathode RF gun Trotz, S.; Brown, W.J.; Danly, B.G.; Hogge, J.; Khusid, M.; Kreischer, K.E.; Shapiro, M.; Temkin, R.J.

Rigid-rotor Vlasov equilibrium for an intense charged-particle beam propagating through a periodic solenoidal magnetic field

2019-04-10T23:14:52Z

Rigid-rotor Vlasov equilibrium for an intense charged-particle beam propagating through a periodic solenoidal magnetic field Chen, C.; Pakter, R.; Davidson, R.C.

Lower bound in energy for chaotic dynamics of ions

2019-04-10T23:14:52Z

Lower bound in energy for chaotic dynamics of ions Benisti, D.; Ram, A.K.; Bers, A.

Two dimensional effects in plasma radiation fronts and radiation front jumps in tokamak divertor plasmas

2019-04-12T20:48:14Z

Two dimensional effects in plasma radiation fronts and radiation front jumps in tokamak divertor plasmas Krasheninnikov, S.I.

Observations of central toroidal rotation in ICRF heated Alcator C-Mod plasmas

2019-04-12T20:48:14Z

Observations of central toroidal rotation in ICRF heated Alcator C-Mod plasmas Rice, J.E.; Greenwald, M.J.; Hutchinson, I.H.; Marmar, E.S.; Takase, Y.; Wolfe, S.M.; Bombarda, F.

Efficient current drive by mode-converted ion-Bernstein waves

2019-04-12T20:48:15Z

Efficient current drive by mode-converted ion-Bernstein waves Ram, A.K.; Bers, A.

Local plasma parameters and H-mode threshold in Alcator C-Mod

2019-04-11T03:13:14Z

Local plasma parameters and H-mode threshold in Alcator C-Mod Hubbard, A.; Goetz, J.A.; Hutchinson, I.H.; In, Y.; Irby, J.; Bombard, B.; Shea, P.J.; Snipes, J.; Stek, P.C.; Takase, Y.; Wolfe, S.M.

Busbar for the low aspect ratio device

2019-04-11T03:13:14Z

Busbar for the low aspect ratio device Bromberg, L.; Sidorov, M.

Pebble bed conductors

2019-04-12T20:48:13Z

Pebble bed conductors Bromberg, L.; Sidorov, M.; Titius, P.

High power operation of a 170 GHz gyrotron for ITER

2019-04-12T20:48:13Z

High power operation of a 170 GHz gyrotron for ITER Kreischer, K.E.; Kimura, T.; Danly, B.G.; Temkin, R.J.

Transport studies in the scrape-off layer and divertor of Alcator C-Mod

2019-04-10T16:50:07Z

Transport studies in the scrape-off layer and divertor of Alcator C-Mod Bombard, B.; Goetz, J.A.; Hutchinson, I.H.; Jablonski, D.; Kesner, J.; Kurz, C.; Lipschultz, B.; Cracken, G.M.; Niemczewski, A.; Terry, J.; Allen, A.; Boivin, R.L.; Bombarda, F.; Bonoli, P.; Christensen, C.; Fiore, C.; Garnier, D.; Golovato, S.

Impurity screening studies in the Alcator C-Mod tokamak

2019-04-10T20:05:16Z

Impurity screening studies in the Alcator C-Mod tokamak Cracken, G.M.; Granetz, R.S.; Lipshultz, B.; Bombard, B.; Terry, J.L.; Bombarda, F.; Goetz, J.A.; Jablonski, D.; Lisgo, S.; Ohkawa, H.; Rice, J.E.; Stangeby, P.C.

Electron heating via mode converted ion Berstein waves in the Alcator C-Mod tokamak

2019-04-12T20:48:14Z

Electron heating via mode converted ion Berstein waves in the Alcator C-Mod tokamak Bonoli, P.T.; Shea, P.; Golovato, S.N.; Hubbard, A.E.; Porkolab, M.; Takase, Y; Boivin, R.L.; Bombarda, F.; Brambilla, M.; Christensen, C.; Fiore, C.; Garnier, D.; Goetz, J.; Granetz, R.; Greenwald, M.; Horne, S.; Hutchinson, I.; Irby, J.; Jablonski, D.

High power density H-modes in Alcator C-Mod

2019-04-10T07:36:22Z

High power density H-modes in Alcator C-Mod Takase, Y.; Boivin, R.; Bombarda, F.; Bonoli, P.; Fiore, C.; Garnier, D.; Goetz, J.; Golovato, S.; Granetz, R.; Greenwald, M.; Horne, S.; Hubbard, A.; Hutchinson, I.; Irby, J.; Bombard, B.; Lipshultz, B.; Marmar, E.; May, M.; Mazurenko, A.; Cracken, G.

Formation and evolution of internal transport barriers in Alcator C-Mod

2019-04-11T03:13:13Z

Formation and evolution of internal transport barriers in Alcator C-Mod Garnier, D.; Marmar, E.; Fiore, C.; Goetz, J.; Golovato, S.; Greenwald, M.; Hubbard, A.; Irby, J.; Shea, P.; Ramos, J.; Rice, J.E.; Schachter, J.M.; Stek, P.C.; Takase, Y.; Watterson, R.L.; Wolfe, S.M.; Martynov, A.

ICRF heating scenarios on Alcator C-Mod

2019-04-12T20:48:11Z

ICRF heating scenarios on Alcator C-Mod Bonoli, P.T.; Golovato, S.; Shea, P.; Porkolab, M.; Takase, Y.; Boivin, R.; Bombarda, F.; Christensen, C.; Fiore, C.; Garnier, D.; Goetz, J.; Granetz, R.; Greenwald, M.; Horne, S.; Hubbard, A.; Hutchinson, I.; Irby, J.; Bombard, B.; Lipschultz, B.

Disruptions, halo currents, and killer pellets in Alcator C-Mod

2019-04-12T20:48:13Z

Disruptions, halo currents, and killer pellets in Alcator C-Mod Granetz, R.S.; Hutchinson, I.H.; Sorci, S.; Garnier, D.; Irby, J.; Bombard, B.; Marmar, E.

Variation of the divertor geometry in Alcator C-Mod

2019-04-12T20:48:10Z

Variation of the divertor geometry in Alcator C-Mod Lipschultz, B.; Goetz, J.; Hutchinson, I.; Bombard, B.; Cracken, G.; Takase, Y.; Terry, J.; Bonoli, P.; Golovato, S.; Shea, P.; Porkolab, M.; Boivin, R.; Bombarda, F.; Fiore, C.; Garnier, D.; Granetz, R.; Greenwald, M.; Horne, S.; Hubbard, A.; Irby, J.

Pyrometry inside an arc furnace using a ray-tracing correction for surface emissivity

2019-04-11T03:13:10Z

Pyrometry inside an arc furnace using a ray-tracing correction for surface emissivity Lee, S.K.; Woskov, P.P.

Fast numerical integration of relaxation oscillator networks based on singular limit solutions

2019-04-11T03:13:11Z

Fast numerical integration of relaxation oscillator networks based on singular limit solutions Lindsey, P.S.; Liang, D.W.

Radiative and 3-body recombination in Alcator C-Mod

2019-04-10T23:14:47Z

Radiative and 3-body recombination in Alcator C-Mod Lumma, D.; Terry, J.L.; Lipschultz, B.

High-field compact divertor tokamak research on Alcator C-Mod

2019-04-10T23:14:47Z

High-field compact divertor tokamak research on Alcator C-Mod Hutchinson, I.H.; Bovin, R.; Bombarda, F.; Bonoli, P.T.; Christensen, C.; Fiore, C.; Garnier, D.; Goetz, J.; Golovato, S.; Granetz, R.; Greenwald, M.; Horne, S.F.; Hubbard, A.; Irby, J.; Jablonski, D.; Bombard, B.; Libshultz, B.; Marmar, E.; May, M.

Enhanced coupling of the fast wave to electrons through mode conversion to the ion hybrid wave

2019-04-12T20:48:09Z

Enhanced coupling of the fast wave to electrons through mode conversion to the ion hybrid wave Davies, C.N.; Fuchs, V.; Ram, A.K.; Bers, A.

Measurements of neutral density based on $H_\alpha$ emissivity in the Alcator C-Mod divertor

2019-04-09T15:57:40Z

Measurements of neutral density based on $H_\alpha$ emissivity in the Alcator C-Mod divertor Kurz, C.; Bombard, B.; Lipschultz, B.; Cracken, G.; Niemczewski, A.; Terry, J.

Negative magnetic shear modes of operation in the Alcator C-Mod tokamak near the beta limit

2019-04-10T19:18:03Z

Negative magnetic shear modes of operation in the Alcator C-Mod tokamak near the beta limit Bonoli, P.T.; Porkolab, M.; Ramos, J.J.; Nevins, W.; Kessel, C.

X-ray observations of central toroidal rotation in ohmic Alcator C-Mod Plasmas

2019-04-10T23:14:41Z

X-ray observations of central toroidal rotation in ohmic Alcator C-Mod Plasmas Rice, J.E.; Marmar, E.S.; Bombarda, F.; Qu, L.

X-ray observations of up-down impurity density asymmetries in Alcator C-Mod plasmas

2019-04-10T23:14:42Z

X-ray observations of up-down impurity density asymmetries in Alcator C-Mod plasmas Rice, J.E.; Terry, E.S.; Marmar, E.S.; Bombarda, F.

Stability of electrostatic modes in a levitated dipole

2019-04-10T23:14:42Z

Stability of electrostatic modes in a levitated dipole Kesner, J.

H-mode confinement in Alcator C-Mod

2019-04-10T23:14:43Z

H-mode confinement in Alcator C-Mod Greenwald, M.; Boivin, R.L.; Bombarda, F.; Bonoli, P.; Fiore, C.; Garnier, D.; Goetz, J.; Golovato, S.; Graf, M.; Granetz, R.; Horne, S.; Hubbard, A.; Hutchinson, I.H.; Irby, J.; Bombard, B.; Lipschultz, B.; Marmar, E.; May, M.; Cracken, G.

MIT Plasma Fusion Center abstracts submitted to the 38th Annual Meeting, APS division of plasma physics 1996

2019-04-09T19:20:41Z

MIT Plasma Fusion Center abstracts submitted to the 38th Annual Meeting, APS division of plasma physics 1996

Halo formation and chaos in RMS-matched beams propagating through a periodic solenoidal focusing channel

2019-04-10T19:08:31Z

Halo formation and chaos in RMS-matched beams propagating through a periodic solenoidal focusing channel Fink, Y.; Chen, C.; Marable, W.P.

Data acquisition system for Alcator C-Mod

2019-04-11T03:13:04Z

Data acquisition system for Alcator C-Mod Fredian, T.F.; Stillerman, J.A.; Greenwald, M.

MDS plus data acquisition system

2019-04-11T03:13:09Z

MDS plus data acquisition system Stillerman, J.A.; Fredian, T.W.; Klare, K.A.; Manduchi, G.

Screening of recycling and non-recycling impurities in the Alcator C-Mod tokamak

2019-04-11T03:13:03Z

Screening of recycling and non-recycling impurities in the Alcator C-Mod tokamak Cracken, G.M.; Granetz, R.S.; Bombard, B.; Bombarda, F.; Goetz, J.A.; Lisgo, S.; Jablonski, D.; Ohkawa, H.; Rice, J.E.; Stangeby, P.C.; Terry, J.L.; Wang, Y.

A comparison of impurity screening between limiter and divertor plasmas in the Alcator C-Mod tokamak

2019-04-10T19:14:21Z

A comparison of impurity screening between limiter and divertor plasmas in the Alcator C-Mod tokamak Granetz, R.; Cracken, G.M.; Bombarda, F.; Goetz, J.A.; Jablonski, D.; Bombard, B.; Lipschultz, B.; Ohkawa, H.; Rice, J.E.; Terry, J.L.; Wang, Y.

Local impurity puffing as a scrape-off layer diagnostic on the Alcator C-Mod tokamak

2019-04-12T20:48:07Z

Local impurity puffing as a scrape-off layer diagnostic on the Alcator C-Mod tokamak Jablonski, D.; Bombard, B.; Cracken, G.M.; Lisgo, S.; Lipschultz, B.; Hutchinson, I.H.; Terry, J.; Stangeby, P.C.

Modification and control of divertor detachment in Alcator C-Mod

2019-04-12T20:48:07Z

Modification and control of divertor detachment in Alcator C-Mod Lipschultz, B.; Goetz, J.A.; Bombard, B.; Cracken, G.M.; Ohkawa, H.; Takase, Y.; Terry, J.L.

Particle drift effects on the Alcator C-Mod divertor

2019-04-12T20:48:07Z

Particle drift effects on the Alcator C-Mod divertor Hutchinson, I.H.; Goetz, J.A.; Jablonski, D.F.; Bombard, B.; Lipschultz, B.; Cracken, G.M.; Snipes, J.; Terry, J.L.; Allen, A.J.; Boivin, P.T.; Bonoli, P.T.; Fiore, C.L.; Granetz, R.S.; Greenwald, M.; Hubbard, A.E.; Marmar, E.S.; Porkolab, M.; Rice, J.E.

Diagnostic neutral beam and active spectroscopy requirements for the Alcator C-Mod tokamak

2019-04-11T03:13:02Z

Diagnostic neutral beam and active spectroscopy requirements for the Alcator C-Mod tokamak Marmar, E.S.; Terry, J.L.; Rowan, W.L.; Wootton, A.J.

Time-of-flight neutral particle analyzer for Alcator C-Mod

2019-04-11T03:13:02Z

Time-of-flight neutral particle analyzer for Alcator C-Mod Boivin, R.L.; Koltonyuk, M.; Munson, C.P.; Mayo, R.M.

Experimental investigation of transport phenomena in the scrape-off layer and divertor

2019-04-12T20:48:07Z

Experimental investigation of transport phenomena in the scrape-off layer and divertor Bombard, B.; Goetz, J.A.; Hutchinson, I.H.; Jablonski, D.; Kesner, J.; Kurz, C; Lipschultz, B.; Cracken, G.M.; Niemczewski, A.; Terry, J.; Allen, A.; Boivin, R.L.; Bomarda, F.; Bonoli, P.; Christensen, C.; Fiore, C.; Garnier, D.; Golovato, S.

Microwave plasma continuous emissions monitor for trace metals

2019-04-12T20:48:04Z

Microwave plasma continuous emissions monitor for trace metals Woskov, P.P.; Rhee, D.Y.; Thomas, P.; Cohn, D.R.; Surma, J.E.; Titus, C.H.

Multi-megawatt relativistic harmonic gyrotron traveling-wave tube amplifier experiments

2019-04-09T15:24:27Z

Multi-megawatt relativistic harmonic gyrotron traveling-wave tube amplifier experiments Menninger, W.L.; Danly, B.G.; Temkin, R.J.

Neutral particle dynamics in the Alcator C-Mod tokamak

2019-04-10T19:56:21Z

Neutral particle dynamics in the Alcator C-Mod tokamak Niemczewski, A.; Hutchinson, I.H.; Bombard, B.; Lipschultz, B.; Cracken, G.M.

The high resolution video capture system on the Alcator C-Mod tokamak

2019-04-12T20:48:06Z

The high resolution video capture system on the Alcator C-Mod tokamak Allen, A.J.; Terry, J.L.; Stillerman, J.A.; Wurden, G.A.

21 - nl' X-ray transitions from neonlike charge states of the row 5 metals with 39[less than or equal to]Z[less than or equal to]46

2019-04-10T07:30:38Z

21 - nl' X-ray transitions from neonlike charge states of the row 5 metals with 39[less than or equal to]Z[less than or equal to]46 Rice, J.E.; Fournier, K.B.; Terry, J.L.; Finkenthal, M.; Marmar, E.S.; Goldstein, W.H.; Safronova, U.I.

Two-body similarity and its violation in tokamak edge plasmas

2019-04-11T03:13:00Z

Two-body similarity and its violation in tokamak edge plasmas Catto, P.J.; Knoll, D.A.; Krasheninnikov, S.I.

Application of collisional-radiative, atomic-molecular model to the recombining divertor plasma

2019-04-11T03:13:01Z

Application of collisional-radiative, atomic-molecular model to the recombining divertor plasma Pigarov, A.Y.; Krasheninnikov, S.I.

MIT Contributions to 5th Plasma edge theory conference

2019-04-12T20:48:03Z

MIT Contributions to 5th Plasma edge theory conference Sigmar, D.J.

Mode conversion of fast Alfven waves at the ion-ion hybrid resonance

2019-04-10T19:34:29Z

Mode conversion of fast Alfven waves at the ion-ion hybrid resonance Ram, A.K.; Bers, A.; Schultz, S.D.; Fuchs, V.

The influence of anomalous diffusion on parallel ion transport in edge plasmas

2019-04-12T20:48:03Z

The influence of anomalous diffusion on parallel ion transport in edge plasmas Helander, P.; Hazeltine, R.D.; Catto, P.J.

Survey of ICRF heating experiments and enhanced performance modes in Alcator C-Mod

2019-04-12T20:48:03Z

Survey of ICRF heating experiments and enhanced performance modes in Alcator C-Mod Takase, Y.; Boivin, R.L.; Bombarda, F.; Bonoli, P.T.; Fiore, C.L.; Marmar, E.S.; Garnier, D.; Goetz, J.A.; Golovato, S.N.; Granetz, R.S.; Rost, C.; Greenwald, M.J.; Horne, S.F.; Hubbard, A.E.; Dimura, H.; Irby, H.; Hutchinson, J.H.

X-ray and VUV observations of Mo23+ - MO33+ brightness profiles from Alcator C-Mod plasmas

2019-04-10T10:33:03Z

X-ray and VUV observations of Mo23+ - MO33+ brightness profiles from Alcator C-Mod plasmas Rice, J.E.; Terry, J.L.; Fournier, K.; May, M.; Marmar, E.S.; Golstein, W.H.; Hubbard, A.E.

H-modes on Alcator C-Mod

2019-04-11T03:13:00Z

H-modes on Alcator C-Mod Snipes, J.A.; Hubbard, A.E.; Garnier, D.T.; Hutchinson, I.H.; Irby, J.; Lambombard, B.; Marmar, E.S.; Niemczewski, A.; Shea, P.J.; Porkolab, M.; Stek, P.; Takase, Y.; Terry, J.L.

Multiple plasma diagnosis from a 5 chord high energy resolution x-ray spectrometer array

2019-04-10T10:33:05Z

Multiple plasma diagnosis from a 5 chord high energy resolution x-ray spectrometer array Rice, J.E.; Bombarda, F.; Graf, M.A.; Marmar, E.S.; Terry, J.L.; Wang, Y.

Theory of hybrid contact discontinuities

2019-04-12T20:48:00Z

Theory of hybrid contact discontinuities Shajii, A.; Freidberg, J.P.

Comparison of detached and radiative divertor operation in Alcator C-Mod

2019-04-10T07:33:28Z

Comparison of detached and radiative divertor operation in Alcator C-Mod Goetz, J.A.; Kurz, C.; Bombard, B.; Lipschultz, B.; Terry, J.L.; Boivin, R.L.; Niemczewski, A.; Cracken, G.M.; Bombarda, F.; Bonoli, P.; Fiore, C.; Golovato, S.; Granetz, R.; Greenwald, M.; Horne, S.

X-ray observations of 2l-nl' transitions from Nr, Nb, Mo and Pd in near neonlike charge stages

2019-04-12T20:48:01Z

X-ray observations of 2l-nl' transitions from Nr, Nb, Mo and Pd in near neonlike charge stages Rice, J.E.; Founier, K.B.; Terry, J.L.; Graf, M.A.; Marmar, E.S.; Finkenthal, M.; Goldtstein, W.H.

The effects of field reversal on the Alcator C-Mod divertor

2019-04-10T10:32:49Z

The effects of field reversal on the Alcator C-Mod divertor Hutchinson, I.H.; Bombard, B.; Goetz, J.A.; Lipschultz, B.; Cracken, G.M.; Snipes, J.A.; Terry, J.L.

Active spectroscopic diagnostics for ITER utilizing neutral beams

2019-04-10T10:32:50Z

Active spectroscopic diagnostics for ITER utilizing neutral beams Marmar, E.S.

Chaotic behavior and halo development in the transverse dynamics of heavy ion beams

2019-04-10T10:32:50Z

Chaotic behavior and halo development in the transverse dynamics of heavy ion beams Chen, C.; Qian, Q.; Davidson, R.

Measuring Implosion Symmetry and Core Conditions in the National Ignition Facility

2019-04-09T18:52:48Z

Measuring Implosion Symmetry and Core Conditions in the National Ignition Facility Petrasso, R.; Li, C.K.; Cable, M.D.; Pollaine, S.M.; Haan, S.W.; Bernat, T.P.; Kilkenny, J.D.; Cremer, S.; Knauer, J.P.; Verdon, C.P.; Kremens, R.L.

Mode conversion heating experiments on Tore Supra

2019-04-10T10:32:57Z

Mode conversion heating experiments on Tore Supra Saoutic, B.

New temperature and metals emissions monitoring technologies for furnaces

2019-04-12T20:47:51Z

New temperature and metals emissions monitoring technologies for furnaces Woskov, P.P.; Cohn, D.R.; Rhee, D.Y.; Thomas, P.; Surma, J.E.; Titus, C.H.

The magnetic presheath boundary condition with ExB drifts

2019-04-09T19:01:49Z

The magnetic presheath boundary condition with ExB drifts Hutchinson, I.H.

Papers presented at the 22nd EPS conference on controlled fusion & plasma physics by the Alcator C-Mod Group

2019-04-12T20:47:51Z

Papers presented at the 22nd EPS conference on controlled fusion & plasma physics by the Alcator C-Mod Group Lipschultz, B.; Crackern, G.; Takase, Y.

Mode-converted ion-Bernstein waves in tokamaks

2019-04-10T10:32:47Z

Mode-converted ion-Bernstein waves in tokamaks Ram, A.K.; Bers, A.; Schultz, S.; Fuchs, V.; Becoulet, A.; Saoutic, B.

Kinetic theory in self-similar variables for neutral atoms in plasma

2019-04-10T10:32:48Z

Kinetic theory in self-similar variables for neutral atoms in plasma Helander, P.; Krasheninnikov, S.I.

Edge turbulence measurements during the L- to H-mode transition by phase contrast imaging on DIII-D

2019-04-10T10:32:48Z

Edge turbulence measurements during the L- to H-mode transition by phase contrast imaging on DIII-D Coda, S.; Porkolab, M.; Burrell, K.H.

Disruptions and halo currents in Alcator C-Mod

2019-04-12T20:47:50Z

Disruptions and halo currents in Alcator C-Mod Granetz, R.S.; Hutchinson, I.H.; Sorci, J.; Irby, J.; Bombard, B.; Gwinn, D.

Collisional damping of the fast magnetosonic wave in the tokamak edge plasma

2019-04-12T20:47:51Z

Collisional damping of the fast magnetosonic wave in the tokamak edge plasma Porkolab, M.; Bonoli, P.T.; Chiu, S.C.

First demonstration of remote tokamak control operation of Alcator C-Mod from LLNL

2019-04-09T15:42:59Z

First demonstration of remote tokamak control operation of Alcator C-Mod from LLNL Horne, S.; Bertolino, V.; Daigle, J.; Fredian, T.; Greenwald, M.; Golovato, S.N.; Hutchinson, I.; Bombard, B.; Stillerman, J.; Takase, Y.; Wolfe, S.

Advanced tokama physics scenarios in Alcator C-Mod

2019-04-12T20:47:50Z

Advanced tokama physics scenarios in Alcator C-Mod Porkolab, M.; Bonoli, P.T.; Golovato, S.; Ramos, J.; Sugiyama, L; Takase, Y.

Plasma-neutral interaction in tokamak divertor for "gas box" neutral model

2019-04-10T10:32:46Z

Plasma-neutral interaction in tokamak divertor for "gas box" neutral model Krasheninnikov, S.I.; Soboleva, T.K.

Plasma reformer/fuel cell system for decentralized power applications

2019-04-10T10:32:46Z

Plasma reformer/fuel cell system for decentralized power applications Bromberg, L.; Cohn, D.R.; Rabinovich, A.

Heating and current drive by mode-converted ion-Bernstein waves

2019-04-10T10:32:47Z

Heating and current drive by mode-converted ion-Bernstein waves Ram, A.K.

Role of edge turbulence in detached divertor plasmas

2019-04-10T10:32:47Z

Role of edge turbulence in detached divertor plasmas Gang, F.Y.; Sigmar, D.J.; Krasheninnikov, S.I.

Efficiency scaling law for the two-stream amplifier

2019-04-12T20:47:49Z

Efficiency scaling law for the two-stream amplifier Chen, C.

A comparison of soft x-ray emissivity contours with magnetic flux surfaces in Alcator C-Mod

2019-04-12T20:47:49Z

A comparison of soft x-ray emissivity contours with magnetic flux surfaces in Alcator C-Mod Borras, M.C.; Granetz, R.S.

RF wave effects on the neoclassical electron distribution function in tokamaks

2019-04-12T20:47:50Z

RF wave effects on the neoclassical electron distribution function in tokamaks Schultz, S.V.; Bers, A.; Ram, A.K.

Flux limiting due to electron impact excitation energy loss

2019-04-10T10:32:46Z

Flux limiting due to electron impact excitation energy loss Catto, P.J.; Krasheninnikov, S.; Hazeltine, R.D.

Scaling laws for two-dimensional divertor modeling

2019-04-09T19:09:44Z

Scaling laws for two-dimensional divertor modeling Catto, P.J.; Krasheninnikov, S.; Connor, J.W.

Theory of low Mach number compressible flow

2019-04-12T20:47:46Z

Theory of low Mach number compressible flow Shajii, A.; Freidberg, J.P.

Radiative instabilities in the tokamak scrape-off layer during edge-localized mode activity

2019-04-12T20:47:47Z

Radiative instabilities in the tokamak scrape-off layer during edge-localized mode activity Helander, P.; Krasheninnikov, S.I.; Morozov, D.; Soboleva, T.K.

Modelling of the transport of the plasma and neutrals in the divertor layer with 1D GARMIT code

2019-04-12T20:47:47Z

Modelling of the transport of the plasma and neutrals in the divertor layer with 1D GARMIT code Kukkushkin, A.S.; Krasheninnikov, S.I.

Self-consistent simulation studies of periodically focused intense charged-particle beams

2019-04-10T19:48:06Z

Self-consistent simulation studies of periodically focused intense charged-particle beams Chen, C.; Jameson, R.A.

Alcator C-Mod papers presented at the 9th joint workshop on electron cyclotron emission and electron cyclotron resonance heating

2019-04-12T20:47:49Z

Alcator C-Mod papers presented at the 9th joint workshop on electron cyclotron emission and electron cyclotron resonance heating Hubbard, A.E.; Hsu, T.C.; Shea, P.J.

Effects of scattering upon energetic ion energy loss

2019-04-10T10:32:44Z

Effects of scattering upon energetic ion energy loss Li, C.K.; Petrasso, R.D.

Graphite millimeter-wave waveguide and mirror for high temperature environments

2019-04-10T10:32:45Z

Graphite millimeter-wave waveguide and mirror for high temperature environments Woskov, P.P.; Titus, C.H.

The visible, imaging diode arrays on Alcator C-Mod

2019-04-10T10:32:45Z

The visible, imaging diode arrays on Alcator C-Mod Terry, J.L.; Snipes, J.A.; Kurz, C.

Spectroscopic measurement of impurity transport coefficients and penetration efficiencies in Alcator C-Mod plasmas

2019-04-12T20:47:45Z

Spectroscopic measurement of impurity transport coefficients and penetration efficiencies in Alcator C-Mod plasmas Graf, M.A.; Rice, J.E.; Terry, J.L.; Goetz, J.A.; Cracken, G.M.; Bombarda, F.; May, M.J.

Theory of thermal hydraulic quenchback

2019-04-12T20:47:44Z

Theory of thermal hydraulic quenchback Shajii, A.; Freidberg, J.P.

Plasma shape control: a general approach and its application to Alcator C-Mod

2019-04-12T20:47:46Z

Plasma shape control: a general approach and its application to Alcator C-Mod Hutchinson, I.H.; Horne, S.; Tinios, G.; Wolfe, S.M.; Granetz, R.S.

Effects of relativistic electrons on the calculated collective thomson scattered spectra

2019-04-12T20:47:44Z

Effects of relativistic electrons on the calculated collective thomson scattered spectra Rhee, D.Y.; Woskov, P.P.; Machuzak, J.S.

Scaling and transport analysis of divertor conditions on the Alcator C-Mod tokamak

2019-04-10T10:32:43Z

Scaling and transport analysis of divertor conditions on the Alcator C-Mod tokamak Bombard, B.; Goetz, J.; Kurz, C.; Jablonksi, D.; Lipschultz, B.; Cracken, G.; Niemczewski, A.; Boivin, R.L.; Bombarda, F.; Christensen, C.; Fairfax, S.; Fiore, C.; Garnier, D.; Graf, M.; Golovato, S.; Granetz, R.; Greenwald, M.; Horne, S.; Hubbard, A.

Transport experiments in Alcator C-Mod

2019-04-10T10:32:43Z

Transport experiments in Alcator C-Mod Greenwald, M.; Boivin, R.L.; Bombarda, F.; Bonoli, P.; Christensen, C.; Fiore, C.; Garnier, D.; Goetz, J.; Golovato, S.; Graf, M.; Granetz, R.; Horne, S.; Hsu, T.; Hubbard, A.; Hutchinson, I.; Irby, J.; Kurz, B.; Bombard, B.; Lipschultz, B.; Luke, T.

Active millimeter-wave pyrometer

2019-04-12T20:47:43Z

Active millimeter-wave pyrometer Woskov, P.P.; Cohn, D.R.; Rhee, D.Y.; Thomas, P.; Titus, C.H.; Surma, J.E.

Performance of the Alcator C-Mod closed divertor in ohmically heated plasmas

2019-04-12T20:47:42Z

Performance of the Alcator C-Mod closed divertor in ohmically heated plasmas Terry, J.L.; Bombarda, F.; Goetz, J.; Graf, M.A.; Kurz, C.; Bombard, B.; Lipschultz, B.; Marmar, E.S.; Cracken, G.M.; Rice, J.E.; Snipes, J.A.; Welch, B.; Boivin, R.L.; Christensen, C.; Fairfax, S.; Fiore, C.; Golovato, S.; Granetz, R.S.; Irby, J.

X-ray observations of 2l - nl[sup prime] transitions in Mo[sup 30+] - Mo[sup 33+] from tokamak plasmas

2019-04-10T07:12:30Z

X-ray observations of 2l - nl[sup prime] transitions in Mo[sup 30+] - Mo[sup 33+] from tokamak plasmas Rice, J.E.; Fournier, K.B.; Graf, M.A.; Terry, J.L.; Finkenthal, M.; Bombarda, F.; Marmar, E.S.; Goldstein, W.H.

Thermal bifurcation of SOL [scrape off layer] plasma and divertor detachment

2019-04-10T10:32:41Z

Thermal bifurcation of SOL [scrape off layer] plasma and divertor detachment Krasheninnikov, S.I.; Sigmar, D.J.; Soboleva, T.K.; Catto, P.J.

Overview of recent results from Alcator C-MOD

2019-04-10T10:32:43Z

Overview of recent results from Alcator C-MOD Porkolab, M.

Confinement of ohmic and ICRF heated plasmas in Alcator C-Mod

2019-04-10T10:32:41Z

Confinement of ohmic and ICRF heated plasmas in Alcator C-Mod Greenwald, M.; Boivin, R.; Bombarda, F.; Bonoli, P.; Christensen, C.; Fairfax, S.; Fiore, C.; Goetz, J.; Golovato, S.; Graf, M.; Granetz, R.; Horne, S.; Hsu, T.; Hubbard, A.; Hutchinson, I.; Irby, J.; Bombard, B.; Lipschultz, B.; Luke, T.; Marmar, E.

Detached scrape-off layer tokamak plasmas

2019-04-10T10:32:42Z

Detached scrape-off layer tokamak plasmas Kesner, J.

RF sources for linear colliders

2019-04-12T20:47:16Z

RF sources for linear colliders Danly, B.G.

Enhanced current drive with lower-hybrid and ion-Bernstein waves

2019-04-12T20:47:17Z

Enhanced current drive with lower-hybrid and ion-Bernstein waves Ram, A.K.; Bers, A.; Fuchs, V.; Schultz, S.D.

Determination of ion temperature with single and triple Langmuir probes

2019-04-09T16:14:57Z

Determination of ion temperature with single and triple Langmuir probes Yang, T.F.; Liu, P.; Zu, Q.X.

Thermal front analysis of detached divertors and Marfes

2019-04-10T10:32:40Z

Thermal front analysis of detached divertors and Marfes Hutchinson, I.H.

Papers presented at the 21st EPS conference on controlled fusion and plasma physics by the Alcator C-MOD group

2019-04-10T10:32:38Z

Papers presented at the 21st EPS conference on controlled fusion and plasma physics by the Alcator C-MOD group Hutchinson, I.H.

Hamiltonian chaos in wave-particle interactions

2019-04-10T10:32:38Z

Hamiltonian chaos in wave-particle interactions Ram, A.K.; Bers, A.

A two-optical-path laser fluorescence signal extraction method

2019-04-10T10:32:39Z

A two-optical-path laser fluorescence signal extraction method Yao, X.Z.; Yang, T.F.; Diaz, F.R.

A dual-cable noise reduction method for Langmuir probes

2019-04-12T20:47:14Z

A dual-cable noise reduction method for Langmuir probes Yang, T.F.; Zu, Q.X.; Liu, P.

A double pendulum precision thrust measurement balance

2019-04-12T20:47:14Z

A double pendulum precision thrust measurement balance Yang, T.F.; Liu, P.; Diaz, F.R.; Lander, H.; Childs, R.A.; Becker, H.D.; Fairfax, S.A.

Current drive by the combination of lower hybrid and ICRF waves

2019-04-10T10:32:37Z

Current drive by the combination of lower hybrid and ICRF waves Ram, A.K.

Effect of diamagnetic and ExB drifts on divertor plasma flows

2019-04-10T10:32:37Z

Effect of diamagnetic and ExB drifts on divertor plasma flows Krashnenninkov, S.; Sigmar, D.; Yushmanov, P.

Scaling of plasma parameters in the SOL and divertor for Alcator C-Mod

2019-04-15T00:37:34Z

Scaling of plasma parameters in the SOL and divertor for Alcator C-Mod Bombard, B.; Jablonski, D.; Lipschultz, G.M.; Cracken, G.M.; Goetz, J.

Power balance and scaling of the radiated power in the divertor and main plasma of Alcator C-Mod

2019-04-09T17:32:05Z

Power balance and scaling of the radiated power in the divertor and main plasma of Alcator C-Mod Goetz, J.; Lipschultz, B.; Graf, M.A.; Kurz, C.; Nachtrieb, R.; Terry, J.L.

Photon activation of the Alcator C-MOD limiter and RF antenna

2019-04-12T20:47:13Z

Photon activation of the Alcator C-MOD limiter and RF antenna Borras, C.

Impurity transport in the divertor of the Alcator C-Mod tokamak

2019-04-12T20:47:12Z

Impurity transport in the divertor of the Alcator C-Mod tokamak Cracken, G.M.; Bombarda, F.; Graf, M.; Goetz, J.A.; Jablonski, D.; Kurz, C.; Labombard, B.; Lipschultz, B.; Rice, J.; Welch, B.

In-situ neutral pressure measurements in a compact high-field tokamak, Alcator C-MOD

2019-04-10T10:32:35Z

In-situ neutral pressure measurements in a compact high-field tokamak, Alcator C-MOD Niemczewski, A.

Impurity sources at the first wall

2019-04-10T10:32:35Z

Impurity sources at the first wall Kurz, C.

Saturation of SRS by spatiotemporal chaos in coupled Langmuir decay

2019-04-12T20:47:07Z

Saturation of SRS by spatiotemporal chaos in coupled Langmuir decay Chow, C.C.; Ram, A.K.; Bers, A.

Dissipative divertor operation

2019-04-12T20:47:08Z

Dissipative divertor operation Lipschultz, B.

Observations of Alcator C-MOD plasmas from a 5 chord high energy resolution x-ray spectrometer array

2019-04-12T20:47:07Z

Observations of Alcator C-MOD plasmas from a 5 chord high energy resolution x-ray spectrometer array Rice, J.E.; Bombarda, F.; Graf, M.A.; Marmar, E.S.; Wang, Y.

Plasma-surface interactions

2019-04-12T20:47:09Z

Plasma-surface interactions Lipschultz, B.

Marfe formation in diverted tokamaks

2019-04-12T20:47:06Z

Marfe formation in diverted tokamaks Kesner, J.; Freidberg, J.P.

A short mean free path, coupled neutron-ion transport description of a tokamak edge plasma

2019-04-10T10:32:24Z

A short mean free path, coupled neutron-ion transport description of a tokamak edge plasma Catto, P.J.

Two-dimensional kinetic modeling of a tokamak scrape-off layer with recycling

2019-04-10T10:32:25Z

Two-dimensional kinetic modeling of a tokamak scrape-off layer with recycling Helander, P.; Catto, P.J.

Soft x-ray silicon photodiodes with 100% quantum efficiency

2019-04-10T10:32:34Z

Soft x-ray silicon photodiodes with 100% quantum efficiency Li, C.K.; Pappas, D.A.; Korde, R.

X-ray observations of helium-like scandium from the Alcator C-Mod tokamak

2019-04-12T20:47:06Z

X-ray observations of helium-like scandium from the Alcator C-Mod tokamak Rice, J.E.; Graf, M.A.; Terry, J.L.; Marmar, E.S.; Giesing, K.; Bombarda, F.

Particle dynamics in chirped-frequency fluctations

2019-04-10T10:32:25Z

Particle dynamics in chirped-frequency fluctations Hsu, C.T.; Cheng, C.Z.; Helander, P.; Sigmar, D.J.; White, R.

First ohmic H-modes in Alcator C MOD

2019-04-10T10:32:33Z

First ohmic H-modes in Alcator C MOD Snipes, J.A.; Granetz, R.S.; Greenwald, M.; Hutchinson, I.H.; Garnier, D.; Goetz, J.A.; Golovato, S.; Hubbard, A.; Irby, J.; Bombard, B.; Luke, T.; Marmar, E.S.; Niemczewski, A.; Stek, P.C.; Takase, Y.; Terry, J.L.; Wolfe, S.M.

Initial millimeter-wave radiometer temperature measurements inside the Mark II arc furnace

2019-04-12T20:47:02Z

Initial millimeter-wave radiometer temperature measurements inside the Mark II arc furnace Woskov, P.P.; Cohn, D.R.; Hamilton, R.A.; Rhee, D.Y.; Surma, J.E.; Sutharshan, B.; Thomas, P.; Titus, C.H.

Anomalous behavior in ICCS

2019-04-10T10:32:21Z

Anomalous behavior in ICCS Bromberg, L.; Takayasu, M.; Schultz, J.H.

Properties of the Kapchinskij-Vladimirskij equilibrium and envelope equation for an intense charged-particle beam in a periodic focusing field

2019-04-10T10:32:21Z

Properties of the Kapchinskij-Vladimirskij equilibrium and envelope equation for an intense charged-particle beam in a periodic focusing field Chen, C.; Davidson, R.C.

Papers presented at the IEEE 15th Symposium on Fusion Engineering by the Alcator C-MOD Group, October 1993

2019-04-10T10:32:23Z

Papers presented at the IEEE 15th Symposium on Fusion Engineering by the Alcator C-MOD Group, October 1993 Fairfax, S.

Alpha particle drive Alfven turbulence and its effect on Alpha transport

2019-04-10T10:32:21Z

Alpha particle drive Alfven turbulence and its effect on Alpha transport Gang, F.Y.; Sigmar, D.J.; Leboeuf, J.; Wising, F.

First results from Alcator C-MOD

2019-04-10T10:32:24Z

First results from Alcator C-MOD Hutchinson, I.H.

Diagnostics for a waste remediation plasma arc furnace

2019-04-12T20:47:00Z

Diagnostics for a waste remediation plasma arc furnace Woskov, P.P.; Cohn, D.R.; Rhee, D.Y.; Titus, C.H.; Wittle, J.K.; Surma, J.E.

Quench in superconducting magnets, part II analytic solution

2019-04-10T10:32:20Z

Quench in superconducting magnets, part II analytic solution Shajii, A.; Freidberg, J.P.

Single-mode operation of a Bragg free-electron Maser oscillator

2019-04-10T10:32:19Z

Single-mode operation of a Bragg free-electron Maser oscillator Chu, T.S.; Hartemann, F.V.; Danly, B.G.; Temkin, R.J.

ITER millimeter-wave CTS diagnostic option

2019-04-12T20:46:59Z

ITER millimeter-wave CTS diagnostic option Woskov, P.P.; Cohn, D.R.; Gilmore, J.; Machuzak, J.S.; Rhee, D.Y.

Experimental study of a 28 GHz high-power long-pulse cyclotron autoresonance maser (CARM) oscillator

2019-04-09T16:02:38Z

Experimental study of a 28 GHz high-power long-pulse cyclotron autoresonance maser (CARM) oscillator Alberti, S.; Danly, B.G.; Gulotta, G.; Giguet, E.; Kimura, T.; Menninger, W.L.; Rullier, J.L.; Temkin, R.J.

LHCD [lower hybrid current drive] accessibility study with reconstructed equilibria in PBX-M

2019-04-12T20:46:58Z

LHCD [lower hybrid current drive] accessibility study with reconstructed equilibria in PBX-M Paoletti, F.; Ignat, D.W.; Kesner, J.; Bernabei, S.; Kaita, R.; Leblanc, B.; Levinton, F.M.; Luckhardt, S.C.

Fast wave flow drive in a two-component plasma with low minority concentration

2019-04-12T11:17:09Z

Fast wave flow drive in a two-component plasma with low minority concentration Gang, F.Y.

The laser-hose instability

2019-04-12T11:17:10Z

The laser-hose instability Shvets, G.; Wurtele, J.S.

Frequency shifting in free electron lasers

2019-04-12T11:17:12Z

Frequency shifting in free electron lasers Shvets, G.; Wurtele, J.S.

Linear and nonlinear analysis of the cyclotron two-stream instability

2019-04-12T20:46:55Z

Linear and nonlinear analysis of the cyclotron two-stream instability Chen, C.; Bekefi, G.; Hu, W.

Electron distribution function measurements on a magnetron injection gun beam

2019-04-12T20:46:56Z

Electron distribution function measurements on a magnetron injection gun beam Guss, W.C.; Basten, M.A.; Kreischer, K.E.; Temkin, R.J.

14 MeV neutron yields from D-T operation of the MIT Cockcroft-Walton accelerator

2019-04-12T20:46:56Z

14 MeV neutron yields from D-T operation of the MIT Cockcroft-Walton accelerator Borras, M.C.; Wenzel, K.W.; Lo, D.H.; Petrasso, R.D.

Plasma heating by fast magnetosonic waves in tokamaks

2019-04-12T20:46:57Z

Plasma heating by fast magnetosonic waves in tokamaks Porkolab, M.

Pierce-type dispersion relation for an intense relativistic electron beam interacting with a slow-wave structure

2019-04-12T11:17:09Z

Pierce-type dispersion relation for an intense relativistic electron beam interacting with a slow-wave structure Chen, C.

Interactions of ICRF waves with lower hybrid driven suprathermal electrons

2019-04-12T11:17:07Z

Interactions of ICRF waves with lower hybrid driven suprathermal electrons Ram, A.K.; Bers, A.; Fuchs, V.; Harvey, R.W.

Anomalous electron streaming due to waves in tokamak plasmas

2019-04-12T11:17:08Z

Anomalous electron streaming due to waves in tokamak plasmas Schultz, S.D.; Bers, A.; Ram, A.K.

Space-time evolution of beam-plasma instability in strongly correlated plasmas

2019-04-12T20:46:53Z

Space-time evolution of beam-plasma instability in strongly correlated plasmas Tao, Z.C.; Ram, A.K.; Bers, A.; Kalman, G.

Lower hybrid current drive in the presence of ion cyclotron waves

2019-04-09T17:03:41Z

Lower hybrid current drive in the presence of ion cyclotron waves Ram, A.K.; Bers, A.; Fuchs, V.

Quench in superconducting magnets. part I: model and numerical implementation

2019-04-12T20:46:54Z

Quench in superconducting magnets. part I: model and numerical implementation Shajii, A.; Freidberg, J.P.

2D full-wave simulation of ordinary mode reflectometry

2019-04-11T04:04:37Z

2D full-wave simulation of ordinary mode reflectometry Irby, J.H.; Horne, S.; Hutchinson, I.H.; Stek, P.C.

Effects of fast Alfven waves in lower-hybrid current drive

2019-04-11T04:04:37Z

Effects of fast Alfven waves in lower-hybrid current drive Ram, A.K.; Bers, A.; Fuchs, V.; Harvey, R.W.; Coy, M.G.

High poloidal beta long pulse experiments in the Tokamak Fusion Test Reactor

2019-04-11T07:12:36Z

High poloidal beta long pulse experiments in the Tokamak Fusion Test Reactor Kesner, J.

Numerical study of relativistic magnetrons

2019-04-12T20:46:40Z

Numerical study of relativistic magnetrons Chan, H.W.

Chaotic stimulated Brillouin scattering in a finite length medium

2019-04-12T20:46:41Z

Chaotic stimulated Brillouin scattering in a finite length medium Chow, C.C.; Bers, A.

Model reduction for axisymmetric tokamak control

2019-04-12T20:46:41Z

Model reduction for axisymmetric tokamak control Tinios, G.; Horne, S.F.; Hutchinson, I.H.; Wolfe, S.M.

Time dependent parallel viscosity and relaxation rate of poloidal rotation in the banana regime

2019-04-12T20:46:43Z

Time dependent parallel viscosity and relaxation rate of poloidal rotation in the banana regime Hsu, C.T.; Shaing, K.C.; Gormley, R.

A series expansion method in three dimensional tomography

2019-04-11T04:04:30Z

A series expansion method in three dimensional tomography Wang, L.; Granetz, R.S.

Mode coupling effects on nonlinear evolution of alpha particle driven Alfven wave instabilities

2019-04-11T04:04:31Z

Mode coupling effects on nonlinear evolution of alpha particle driven Alfven wave instabilities Gang, F.Y.; Lebeouf, J.N.

Response of X-UV photodiodes from 1.5 keV - 17.5 keV x rays and MeV alpha particles

2019-04-11T04:04:32Z

Response of X-UV photodiodes from 1.5 keV - 17.5 keV x rays and MeV alpha particles Wenzel, K.W.; Li, C.K.; Petrasso, R.D.; Lo, D.H.; Bautz, M.W.; Ricker, G.R.; Hsieh, E.

Spatiotemporial chaos in three wave interactions

2019-04-11T04:04:32Z

Spatiotemporial chaos in three wave interactions Chow, C.C.; Bers, A.; Ram, A.K.

Charged-particle stopping powers in inertial confinement fusion plasmas

2019-04-10T20:12:27Z

Charged-particle stopping powers in inertial confinement fusion plasmas Li, C.K.; Petrasso, R.D.

A Fokker-Planck equation for moderately coupled plasmas

2019-04-12T20:46:35Z

A Fokker-Planck equation for moderately coupled plasmas Li, C.K.; Petrasso, R.D.

Growth and saturation of stimulated beam modulation in a two-stream relativistic klystron amplifier

2019-04-12T20:46:32Z

Growth and saturation of stimulated beam modulation in a two-stream relativistic klystron amplifier Chen, C.; Catravas, P.; Bekefi, G.

Large-amplitude traveling electromagnetic waves in collisionless magnetoplasmas

2019-04-11T04:04:28Z

Large-amplitude traveling electromagnetic waves in collisionless magnetoplasmas Chen, C.; Davies, J.A.; Wurtele, J.S.; Zhang, G.

Effect of anomalous alpha diffusion on fusion power coupling into tokamak plasma

2019-04-11T04:04:29Z

Effect of anomalous alpha diffusion on fusion power coupling into tokamak plasma Sigmar, D.J.; Gormley, R.; Kamelander, G.

Why beta\sub p\ and l\sub i\ cannot be separately measured in a near circular tokamak

2019-04-11T03:53:59Z

Why beta\sub p\ and l\sub i\ cannot be separately measured in a near circular tokamak Friedberg, J.P.; Graf, M.; Niemczewski, A.; Schultz, S.; Shajii, A.

Bootstrap current induced by fusion born alpha particles

2019-04-12T20:46:07Z

Bootstrap current induced by fusion born alpha particles Hsu, C.T.; Shaing, K.T.; Sigmar, D.J.; Gormley, R.

Theory of electron cyclotron resonance laser accelerators

2019-04-12T20:46:08Z

Theory of electron cyclotron resonance laser accelerators Chen, C.

Hermitian description of interacting inhomogeneous electron beams

2019-04-12T20:46:06Z

Hermitian description of interacting inhomogeneous electron beams Friedland, L.; Bers, A.

Time dependent effects of fusion reactivity enhancement due to minority heating in D-T and D-/super 3/He tokamak plasmas

2019-04-12T20:46:08Z

Time dependent effects of fusion reactivity enhancement due to minority heating in D-T and D-/super 3/He tokamak plasmas Chaniotakis, E.A.; Sigmar, D.J.

A proton activation diagnostic to measure D-/super 3/He reaction yields

2019-04-10T17:22:36Z

A proton activation diagnostic to measure D-/super 3/He reaction yields Lierzer, J.R.; Wenzel, K.W.; Petrasso, R.D.; Lo, D.H.; Coleman, J.W.; Li, C.K.; Hsieh, E.; Bernat, T.

Response of SBDs to MeV protons, tritons and alphas: evidence that the charged particle sensitive depth is not generally the depletion layer depth

2019-04-10T17:22:36Z

Response of SBDs to MeV protons, tritons and alphas: evidence that the charged particle sensitive depth is not generally the depletion layer depth Lo, D.H.; Petrasso, R.D.; Wenzel, K.W.; Coleman, J.W.; Li, C.K.; Lierzer, J.R.

PIXE x-rays: from Z=4 to Z=92

2019-04-12T20:45:56Z

PIXE x-rays: from Z=4 to Z=92 Li, C.K.; Wenzel, K.W.; Petrasso, R.D.; Lo, D.H.; Coleman, J.W.; Lierzer, J.R.; Hsieh, E.; Bernat, T.; Hsieh, E.; Bernat, T.

Performance evaluation of the TFTR gyrotron CTS diagnostic for alpha particles

2019-04-09T15:35:04Z

Performance evaluation of the TFTR gyrotron CTS diagnostic for alpha particles Rhee, D.Y.; Cohn, D.R.; Machuzak, J.S.; Woskov, P.; Bretz, N.; Budny, R.; Efthimion, P.C.; Park, H.K.

MIT modular x-ray source systems for the study of plasma diagnostics

2019-04-12T20:46:02Z

MIT modular x-ray source systems for the study of plasma diagnostics Coleman, J.W.; Wenzel, K.W.; Petrasso, R.D.; Lo, D.H.; Li, C.K.; Lierzer, J.R.; Wei, T.

Localized magnetic field pitch angle measurements by collective Thomson scattering

2019-04-11T03:41:52Z

Localized magnetic field pitch angle measurements by collective Thomson scattering Woskov, P.P.; Rhee, D.Y.

The three wave interaction and spatiotemporal chaos

2019-04-10T17:22:29Z

The three wave interaction and spatiotemporal chaos Chow, C.C.; Bers, A.; Ram, A.K.

One-dimensional full-wave analysis of reflectrometry sensitivity and correlations

2019-04-10T17:22:28Z

One-dimensional full-wave analysis of reflectrometry sensitivity and correlations Hutchinson, I.H.

Spatiotemporal chaos in the nonlinear three wave interaction

2019-04-10T17:22:29Z

Spatiotemporal chaos in the nonlinear three wave interaction Chow, C.C.; Bers, A.; Ram, A.K.

Lower-hybrid and fast Alfven wave current drive -- status of theory

2019-04-12T20:45:52Z

Lower-hybrid and fast Alfven wave current drive -- status of theory Bers, A.; Ram, A.K.

Theory of energetic alpha particle driven Alfven wave turbulence

2019-04-12T20:45:53Z

Theory of energetic alpha particle driven Alfven wave turbulence Gang, F.

MIT fusion [gamma]-ray diagnostic development

2019-04-12T20:45:54Z

MIT fusion [gamma]-ray diagnostic development Wenzel, K.W.; Petrasso, R.D.; Lo, D.H.; Li, C.K.; Coleman, J.W.; Lierzer, J.R.; Hsieh, E.; Bernat, T.

A fusion-product source

2019-04-12T20:45:56Z

A fusion-product source Wenzel, K.W.; Lo, D.H.; Petrasso, R.D.; Coleman, J.W.; Li, C.K.; Lierzer, J.R.; Borras, C.; Wei, T.; Hsieh, E.; Bernat, T.

Comment on "cluster-impact fusion"

2019-04-10T17:22:28Z

Comment on "cluster-impact fusion" Lo, D.H.; Petrasso, R.D.; Wenzel, K.W.

Axisymmetric structural simulation of the central solenoid for the Burning Plasma Experiment (BPX)

2019-04-12T20:45:50Z

Axisymmetric structural simulation of the central solenoid for the Burning Plasma Experiment (BPX) Myatt, R.L.

Papers presented at the IEEE 14th Symposium on Fusion Engineering by the Alcator C-MOD engineering staff, Oct. 1991

2019-04-10T20:53:58Z

Papers presented at the IEEE 14th Symposium on Fusion Engineering by the Alcator C-MOD engineering staff, Oct. 1991 Fairfax, S.; Beck, W.; Becker, H.; Titus, P.; Bosco, J.; Burke, W.M.; Daigle, J.; Sueker, K.; Fuller, T.P.; Fiore, C.L.; Bombard, B.; Lipschultz, B.; Kochan, S.; Paranay, J.S.; Parkin, W.; Takase, Y.; Golovato, S.; Porkolab, M.

Alpha particle losses from toroidicity induced Alfven eigenmodes: Part I: Phase-space topology of energetic orbits in tokamak plasma

2019-04-12T20:45:47Z

Alpha particle losses from toroidicity induced Alfven eigenmodes: Part I: Phase-space topology of energetic orbits in tokamak plasma Hsu, C.T.; Sigmar, D.J.

Alpha particle losses from toroidicity induced Alfven eigenmodes: Part II: Monte Carlo simulations and anomalous alpha loss processes

2019-04-12T20:45:47Z

Alpha particle losses from toroidicity induced Alfven eigenmodes: Part II: Monte Carlo simulations and anomalous alpha loss processes Sigmar, D.J.; Hsu, C.T.; White, R.; Cheng, C.Z.

Compendium of papers by the fusion reactor studies group

2019-04-12T20:45:51Z

Compendium of papers by the fusion reactor studies group Bathke, C.G.; Bromberg, L.; Chaniotakis, E.A.; Cheng, E.T.; Cohn, D.; Krakowski, R.A.; Claire, R.; Najmabadi, F.; Schultz, J.; Sharafat, S.; Titus, P.; Wang, P.; Williams, J.E.

Stability of Alfven gap modes in burning plasmas

2019-04-10T17:22:25Z

Stability of Alfven gap modes in burning plasmas Betti, R.; Freidberg, J.P.

Effect of longitudinal space-charge waves of a helical relativistic electron beam on the cyclotron maser instability

2019-04-10T17:22:25Z

Effect of longitudinal space-charge waves of a helical relativistic electron beam on the cyclotron maser instability Chen, C.; Danly, B.G.; Shvets, G.; Wurtele, J.S.

Numerical studies of the spectral evolution of a narrow-bandwidth FEL oscillator

2019-04-10T17:22:26Z

Numerical studies of the spectral evolution of a narrow-bandwidth FEL oscillator Yang, T.; Temkin, R.J.; Wurtele, J.S.; Chen, S.C.; Danly, B.G.

Saturation of energetic particle driven Alfven wave instability through velocity space diffusion

2019-04-12T20:45:47Z

Saturation of energetic particle driven Alfven wave instability through velocity space diffusion Gang, F.Y.; Sigmar, D.J.; Leboeuf, J.N.

Effects of heating profile on energy transport in neutral beam heated TFTR plasmas

2019-04-09T16:14:35Z

Effects of heating profile on energy transport in neutral beam heated TFTR plasmas Takase, Y.; Goldston, R.J.; Bell, M.; Bitter, M.; Bush, C.E.; Cavallo, A.; Diamond, P.H.; Efthimion, P.C.; Ehrhardt, A.; Fonck, R.; Frederickson, E.D.; Grek, B.; Hammett, G.W.; Hawryluk, R.J.; Heifetz, D.; Hendel, H.; Hill, K.W.; Howell, B.; Jaehnig, K.

Scaling laws for the cyclotron resonance laser accelerator

2019-04-10T17:22:24Z

Scaling laws for the cyclotron resonance laser accelerator Chen, C.

Maximizing absorption in ion-cyclotron heating of tokamak plasmas

2019-04-11T07:12:30Z

Maximizing absorption in ion-cyclotron heating of tokamak plasmas Bers, A.; Fuchs, V.; Chow, C.C.

Experimental study of a 33.3 GHz free electron laser amplifier with a reversed axial guide magnetic field

2019-04-09T15:57:38Z

Experimental study of a 33.3 GHz free electron laser amplifier with a reversed axial guide magnetic field Conde, M.E.; Bekefi, G.

Neutral hydrogen density measurement in TMSPP

2019-04-10T17:22:24Z

Neutral hydrogen density measurement in TMSPP Yao, X.Z.; Yang, T.F.; Diaz, F.R.

Fast electron transport in lower-hybrid current drive

2019-04-12T20:45:46Z

Fast electron transport in lower-hybrid current drive Kupfer, K.; Bers, A.

Parametric studies of free electron laser nonlinear ponderomotive trapping buckets

2019-04-12T20:45:46Z

Parametric studies of free electron laser nonlinear ponderomotive trapping buckets Fajans, J.; Chu, R.; Wurtele, J.S.

Fusion energy--the moment of truth nears

2019-04-12T20:45:46Z

Fusion energy--the moment of truth nears Petrasso, R.D.

Double stream cyclotron maser

2019-04-10T19:40:39Z

Double stream cyclotron maser Bekefi, G.

Steady state and time dependent effects of fusion reactivity enhancement due to minority heating in D-T and D-/super 3/He tokamak plasmas

2019-04-10T17:22:23Z

Steady state and time dependent effects of fusion reactivity enhancement due to minority heating in D-T and D-/super 3/He tokamak plasmas Chaniotakis, E.A.; Sigmar, D.J.

Absolute versus convective analysis of instabilities in space plasmas

2019-04-10T17:22:23Z

Absolute versus convective analysis of instabilities in space plasmas Ram, A.K.; Bers, A.

Possibilities for long pulse ignited tokamak experiments using resistive magnets

2019-04-11T07:12:28Z

Possibilities for long pulse ignited tokamak experiments using resistive magnets Chaniotakis, E.A.; Bromberg, L.; Cohn, D.R.

The X-ray imaging diagnostics of Alcator C-MOD

2019-04-09T19:15:20Z

The X-ray imaging diagnostics of Alcator C-MOD Granetz, R.

Elliptically induced Alfven eigenmodes

2019-04-10T17:22:05Z

Elliptically induced Alfven eigenmodes Betti, R.; Freidberg, J.P.

Comments on absolute and convective instabilities

2019-04-12T20:45:45Z

Comments on absolute and convective instabilities Ram, A.K.; Bers, A.

Fast electron transport during lower-hybrid current drive

2019-04-12T20:45:45Z

Fast electron transport during lower-hybrid current drive Kupfer, K.; Bers, A.; Ram, A.K.

Linear and nonlinear theory of cyclotron autoresonance masers with multiple waveguide modes

2019-04-09T17:45:06Z

Linear and nonlinear theory of cyclotron autoresonance masers with multiple waveguide modes Chen, C.; Wurtele, J.S.

Experimental and theoretical studies of a 35 GHz cyclotron autoresonance maser amplifier

2019-04-10T17:22:02Z

Experimental and theoretical studies of a 35 GHz cyclotron autoresonance maser amplifier Rienzo, A.C.; Bekefi, G.; Chen, C.; Wurtele, J.S.

Induction linac driven relativistic klystron and cyclotron autoresonance maser experiments

2019-04-10T17:22:05Z

Induction linac driven relativistic klystron and cyclotron autoresonance maser experiments Goodman, D.L.; Birx, D.L.; Danly, B.G.

Design optimization of ignited tokamaks

2019-04-10T19:38:13Z

Design optimization of ignited tokamaks Chaniotakis, E.A.; Freidberg, J.P.; Cohn, D.R.

Innovative design option for internal coils

2019-04-12T20:45:36Z

Innovative design option for internal coils Bromberg, L.; Tillack, M.S.

CIT elongation tradeoffs studies

2019-04-09T17:52:42Z

CIT elongation tradeoffs studies Bromberg, L.; Wei, J.

Multimode interactions in cyclotron autoresonance maser amplifiers

2019-04-11T07:38:10Z

Multimode interactions in cyclotron autoresonance maser amplifiers Chen, C.; Wurtele, J.

Direct spectral measurements of a quasi-cw free-electron laser oscillator

2019-04-11T03:55:25Z

Direct spectral measurements of a quasi-cw free-electron laser oscillator Danly, B.G.; Evangelides, S.G.; Chu, T.S.; Temkin, R.J.; Ramian, G.; Hu, J.

Research at MIT on high frequency gyrotrons for ECRH

2019-04-10T17:22:00Z

Research at MIT on high frequency gyrotrons for ECRH Kreischer, K.E.; Grimm, T.L.; Guss, W.C.; Temkin, R.J.; Xu, K.Y.

CARM amplifier theory and simulation

2019-04-12T20:45:36Z

CARM amplifier theory and simulation Chen, C.; Danly, B.G.; Davies, J.A.; Menninger, W.L.; Wurtele, J.S.; Zhang, G.

Sawteeth effects on burn control

2019-04-12T20:45:36Z

Sawteeth effects on burn control Chaniotakis, E.A.; Bromberg, L.; Cohn, D.R.

The connected presheath: one-dimensional models of neighbouring objects in magnetized plasmas

2019-04-12T20:45:34Z

The connected presheath: one-dimensional models of neighbouring objects in magnetized plasmas Hutchinson, I.H.

Operation of a long-pulse CARM oscillator

2019-04-12T20:45:35Z

Operation of a long-pulse CARM oscillator Pendergast, K.D.; Danly, B.G.; Temkin, R.J.

A stability criterion for energetic particle-Alfven modes

2019-04-09T18:25:33Z

A stability criterion for energetic particle-Alfven modes Betti, R.; Freidberg, J.P.

Nonlinear impurity transport including bifurcations and coupling to rippling mode

2019-04-11T07:38:05Z

Nonlinear impurity transport including bifurcations and coupling to rippling mode Sigmar, D.J.; Lee, G.S.; Hsu, C.T.; Wenzel, K.W.

Magnet design for the ARIES-I high-field tokamak reactor

2019-04-11T07:38:08Z

Magnet design for the ARIES-I high-field tokamak reactor Bromberg, L.; Cohn, D.R.; Schultz, J.; Schwartz, J.; Titus, P.; Williams, J.E.; Grotz, S.P.; Creedon, R.L.; Wong, C.P.

Complete macroscopic stabilization of tokamak plasmas

2019-04-11T07:38:10Z

Complete macroscopic stabilization of tokamak plasmas Ramos, J.J.

Dynamic stability of edge cooled superconducting tapes

2019-04-11T10:02:43Z

Dynamic stability of edge cooled superconducting tapes Schwartz, J.; Freidberg, J.P.; Williams, J.E.

A high-voltage modulator for high-power RF source research

2019-04-12T20:44:53Z

A high-voltage modulator for high-power RF source research Mulligan, W.; Chen, S.C.; Bekefi, G.; Danly, B.G.; Temkin, R.J.

Fast wave ion cyclotron resonance heating experiments on the Alcator C tokamak

2019-04-09T15:49:05Z

Fast wave ion cyclotron resonance heating experiments on the Alcator C tokamak Shepard, T.D.; Fiore, C.L.; Dermott, F.S.; Parker, R.R.; Porkolab, M.

Bandwidth of scattered radiation in laser-plasma interactions

2019-04-11T10:02:42Z

Bandwidth of scattered radiation in laser-plasma interactions Chow, C.C.; Ram, A.K.; Bers, A.

Design of a 3rd harmonic electron cyclotron emission diagnostic for ballooning mode fluctuations in PBX-M

2019-04-11T10:02:26Z

Design of a 3rd harmonic electron cyclotron emission diagnostic for ballooning mode fluctuations in PBX-M Woskov, P.P.; Kesner, J.; Lane, B.; Luckhardt, S.; Machuzak, J.S.; Rhee, D.; Cohn, D.R.

Guiding center stochasticity and transport induced by electrostatic waves

2019-04-12T20:44:44Z

Guiding center stochasticity and transport induced by electrostatic waves Kupfer, K.; Bers, A.; Ram, A.K.

Chaotic electron dynamics for relativistic electron beam propagation through a planar-wiggler magnetic field

2019-04-12T20:44:47Z

Chaotic electron dynamics for relativistic electron beam propagation through a planar-wiggler magnetic field Chen, C.; Davidson, R.C.

Velocity ratio measurements of a gyrotron electron beam

2019-04-10T18:15:01Z

Velocity ratio measurements of a gyrotron electron beam Guss, W.C.; Grimm, T.L.; Kreischer, K.E.; Polevoy, J.T.; Temkin, R.J.

Calculated collective Thomson scattered spectra from energetic ions in tokamaks

2019-04-09T19:04:14Z

Calculated collective Thomson scattered spectra from energetic ions in tokamaks Rhee, D.Y.; Machuzak, J.S.; Woskov, P.P.; Cohn, D.R.; Myer, R.C.

Propagation and damping of mode converted ion-Bernstein waves in toroidal plasmas

2019-04-11T10:02:23Z

Propagation and damping of mode converted ion-Bernstein waves in toroidal plasmas Ram, A.K.; Bers, A.

The neutron diagnostic experiment for Alcator C-MOD

2019-04-10T18:15:05Z

The neutron diagnostic experiment for Alcator C-MOD Fiore, C.L.; Granetz, R.S.

Measurement of the internal magnetic field in tokamaks utilizing impurity pellets: a new detection technique

2019-04-11T02:44:45Z

Measurement of the internal magnetic field in tokamaks utilizing impurity pellets: a new detection technique Marmar, E.S.; Terry, J.L.

Macroclump model of the nonlinear evolution of the sideband instability in a helical wiggler free electron laser

2019-04-12T20:44:33Z

Macroclump model of the nonlinear evolution of the sideband instability in a helical wiggler free electron laser Yang, T.; Davidson, R.C.

Magnetic diagnostics in Alcator C-MOD

2019-04-12T20:44:35Z

Magnetic diagnostics in Alcator C-MOD Granetz, R.S.; Hutchinson, I.H.; Gerolamo, J.; Pina, W.; Tsui, C.

Parametric instabilities in the tokamak edge plasma in the ion cyclotron heating regimes

2019-04-09T16:09:24Z

Parametric instabilities in the tokamak edge plasma in the ion cyclotron heating regimes Porkolab, M.

Influence of trapped-electron distribution on the sideband instability in a helical wiggler free electron laser

2019-04-10T18:15:00Z

Influence of trapped-electron distribution on the sideband instability in a helical wiggler free electron laser Yang, T.; Davidson, R.C.

Operation of a long-pulse relativistic magnetron in a phase-locking system

2019-04-11T02:44:44Z

Operation of a long-pulse relativistic magnetron in a phase-locking system Chen, S.C.; Bekefi, G.; Temkin, R.

An improved design for quasi-optical mode conversion of whispering gallery mode gyrotron radiation

2019-04-10T18:15:01Z

An improved design for quasi-optical mode conversion of whispering gallery mode gyrotron radiation Mobius, A.W.; Casey, J.A.; Kreischer, K.E.; Li, A.; Temkin, R.J.

Observations of periodic intensity bursts from a free electron oscillator

2019-04-12T20:44:32Z

Observations of periodic intensity bursts from a free electron oscillator Jerby, E.; Bekefi, G.; Wurtele, J.S.

Chaotic particle dynamics in free electron lasers

2019-04-12T20:44:31Z

Chaotic particle dynamics in free electron lasers Chen, C.; Davidson, R.C.

Reflection at the resonance layer of the fast Alfven wave in ion cyclotron heating

2019-04-11T02:44:44Z

Reflection at the resonance layer of the fast Alfven wave in ion cyclotron heating Chow, C.; Fuchs, V.; Bers, A.

Large-amplitude coherent structures in nonneutral plasmas with circulating electron flow

2019-04-12T20:44:26Z

Large-amplitude coherent structures in nonneutral plasmas with circulating electron flow Davidson, R.C.; Chan, H.W.; Chen, C.; Lund, S.

Computer simulation of relativistic multiresonator cylindrical magnetrons

2019-04-12T20:44:26Z

Computer simulation of relativistic multiresonator cylindrical magnetrons Chan, H.W.; Chen, C.; Davidson, R.C.

High gain requirements and high field tokamak experiments

2019-04-12T20:44:26Z

High gain requirements and high field tokamak experiments Cohn, D.R.

Possible achievement of second stability by means of lower hybrid current drive

2019-04-11T02:44:44Z

Possible achievement of second stability by means of lower hybrid current drive Bonoli, P.T.; Porkolab, M.; Ramos, J.; Blackfield, D.T.; Devoto, R.; Fenstermacher, M.E.

Non-linear theory and experiment of collective free electron lasers

2019-04-11T02:44:43Z

Non-linear theory and experiment of collective free electron lasers Wurtele, J.S.; Chu, R.; Fajans, J.

Eulerian formalism of linear beam-wave interactions

2019-04-11T02:44:43Z

Eulerian formalism of linear beam-wave interactions Hartemann, F.

Relativistic electrodynamics of nonlinear media

2019-04-12T15:40:34Z

Relativistic electrodynamics of nonlinear media Hartemann, F.; Toffano, Z.

The tokamak [beta]aB/I limit and its dependence on the safety factor

2019-04-12T15:40:34Z

The tokamak [beta]aB/I limit and its dependence on the safety factor Ramos, J.J.

ICRF-edge plasma interaction studies at MIT

2019-04-12T15:40:34Z

ICRF-edge plasma interaction studies at MIT Golovato, S.N.; Porkolab, M.; Takase, Y.; Bombard, B.; Shea, P.; Reardon, J.; Terwilliger, R.

Alternate representation of the dielectric tensor for a relativistic magnetized plasma in thermal equilibrium

2019-04-12T20:44:24Z

Alternate representation of the dielectric tensor for a relativistic magnetized plasma in thermal equilibrium Yoon, P.H.; Davidson, R.C.

Anomalous (stimulated) refraction induced by the free-electron laser interaction

2019-04-10T18:14:59Z

Anomalous (stimulated) refraction induced by the free-electron laser interaction Hartemann, F.; Mourier, G.; Davidson, R.C.

A planar electromagnet microwiggler for free electron lasers

2019-04-10T18:14:55Z

A planar electromagnet microwiggler for free electron lasers Stoner, R.; Chen, S.C.; Bekefi, G.

Transport induced by ion-impurity friction in strongly rotating, collisional tokamak plasma

2019-04-10T18:14:55Z

Transport induced by ion-impurity friction in strongly rotating, collisional tokamak plasma Hsu, C.T.; Sigmar, D.J.

Slotted resonator gyrotron experiments

2019-04-10T18:14:57Z

Slotted resonator gyrotron experiments Hakkarainen, S.; Kreischer, K.E.; Temkin, R.J.

Programs for computing cyclotron-resonance-maser absolute instability properties

2019-04-12T20:44:23Z

Programs for computing cyclotron-resonance-maser absolute instability properties Zhang, G.; Davies, J.A.; Johnston, G.L.

Kinetic ray tracing in toroidal geometry with application to mode-converted ion-Bernstein waves

2019-04-10T18:14:51Z

Kinetic ray tracing in toroidal geometry with application to mode-converted ion-Bernstein waves Ram, A.; Bers, A.

Plasma current profile control and high [beta] operation in tokamaks with D-shaped plasma

2019-04-12T20:44:21Z

Plasma current profile control and high [beta] operation in tokamaks with D-shaped plasma Yang, T.F.; Luan, G.S.

Self-field-induced chaotic electron motion in free electron lasers

2019-04-09T17:32:03Z

Self-field-induced chaotic electron motion in free electron lasers Chen, C.; Davidson, R.C.

Growth and frequency pushing effects in magnetron phase-locking

2019-04-12T20:44:22Z

Growth and frequency pushing effects in magnetron phase-locking Chen, S.C.

Submillimeter wave harmonic gyrotron experiment

2019-04-12T20:44:22Z

Submillimeter wave harmonic gyrotron experiment Hakkarainen, S.; Kreischer, K.E.; Temkin, R.J.

The ICRF dispersion relation for D(/super 3/He)

2019-04-12T20:44:22Z

The ICRF dispersion relation for D(/super 3/He) Chow, C.; Fuchs, V.; Bers, A.

Experimental study of multiple frequency effects in a free electron laser amplifier

2019-04-10T18:14:50Z

Experimental study of multiple frequency effects in a free electron laser amplifier Xu, K.; Bekefi, G.

Measurements of neutron emission induced by muons stopped in metal deuteride targets

2019-04-10T18:14:51Z

Measurements of neutron emission induced by muons stopped in metal deuteride targets Chen, M.; Steadman, S.G.; Gaudreau, M.P.; Luckhardt, S.C.; Parker, R.R.; Albagli, D.; Cammarata, V.; Schloh, M.; Wrighton, M.S.; Kwok, K.; Thieme, C.; Lowenstein, D.I.; Debbe, R.; Reilly, J.J.

Measurement and analysis of neutron and gamma ray emission rates, other fusion products, and power in electrochemical cells having Pd cathodes

2019-04-12T20:44:21Z

Measurement and analysis of neutron and gamma ray emission rates, other fusion products, and power in electrochemical cells having Pd cathodes Albagli, D.; Ballinger, R.; Cammarata, V.; Chen, X.; Crooks, R.; Fiore, C.; Gaudreau, M.; Hwang, I.; Li, C.K.; Linsay, P.; Luckhardt, S.; Parker, R.R.; Petrasso, R.; Schloh, M.; Wenzel, K.; Wrighton, M.

Filament-circuit analysis of Alcator C-MOD vertical stability

2019-04-09T17:23:08Z

Filament-circuit analysis of Alcator C-MOD vertical stability Humphreys, D.A.; Hutchinson, I.H.

Pulse shapes for absolute and convective cyclotron-resonance-maser instabilities

2019-04-10T18:14:48Z

Pulse shapes for absolute and convective cyclotron-resonance-maser instabilities Davies, J.A.; Davidson, R.C.; Johnston, G.L.

Self-field-induced chaoticity in the electron orbits in a helical-wiggler free electron laser with axial guide field

2019-04-10T18:14:49Z

Self-field-induced chaoticity in the electron orbits in a helical-wiggler free electron laser with axial guide field Chen, C.; Davidson, R.C.

Theory and experimental review of plasma contactors

2019-04-12T20:44:19Z

Theory and experimental review of plasma contactors Gerver, M.J.; Hastings, D.E.; Oberhardt, M.R.

Experimental study of a high frequency, megawatt gyrotron oscillator

2019-04-12T20:44:20Z

Experimental study of a high frequency, megawatt gyrotron oscillator Kreischer, K.E.; Guss, W.C.; Temkin, R.J.

[Gamma]-ray spectra in the Fleischmann, Pons, Hawkins experiment

2019-04-10T18:14:46Z

[Gamma]-ray spectra in the Fleischmann, Pons, Hawkins experiment Petrasso, R.D.; Chen, X.; Wenzel, K.W.; Parker, R.R.; Li, C.K.; Fiore, C.

Nonlinear theory of quasi-optical gyrotron with an electron beam at an oblique angle

2019-04-12T20:44:18Z

Nonlinear theory of quasi-optical gyrotron with an electron beam at an oblique angle Wang, C.; Kreischer, K.; Temkin, R.

Achievement of second stability by means of lower hybrid current drive

2019-04-12T20:44:19Z

Achievement of second stability by means of lower hybrid current drive Bonoli, P.T.; Porkolab, M.; Blackfield, D.T.; Devoto, R.S.; Fenstermacher, M.E.

Linear theory of the collective Raman interaction in a free-electron laser with a planar wiggler and an axial guide field

2019-04-12T20:44:19Z

Linear theory of the collective Raman interaction in a free-electron laser with a planar wiggler and an axial guide field Freund, H.P.; Davidson, R.C.; Johnston, G.L.

Plasma flow measurements along the presheath of a magnetized plasma

2019-04-09T18:35:30Z

Plasma flow measurements along the presheath of a magnetized plasma Chung, K.; Hutchinson, I.H.; Bombard, B.; Conn, R.W.

Electrostatic barrier scrape-off layer as a technique to reduce impurity sources from plasma bombardment of RF antenna structures

2019-04-10T18:14:45Z

Electrostatic barrier scrape-off layer as a technique to reduce impurity sources from plasma bombardment of RF antenna structures Bombard, B.

Damping of the fast Alfven wave in ion-cyclotron resonance heating

2019-04-10T18:14:42Z

Damping of the fast Alfven wave in ion-cyclotron resonance heating Chow, C.; Ram, A.K.; Bers, A.

Prebunching in a collective Raman free electron laser amplifier

2019-04-09T16:55:42Z

Prebunching in a collective Raman free electron laser amplifier Wurtele, J.S.; Bekefi, G.; Chu, R.; Xu, K.

Simplified models of axisymmetric MHD instabilities

2019-04-12T20:44:15Z

Simplified models of axisymmetric MHD instabilities Hutchinson, I.H.

Waveguide mode deformation in free electron lasers

2019-04-11T01:37:56Z

Waveguide mode deformation in free electron lasers Fajans, J.; Wurtele, J.S.

Prospects for a high field ITER device

2019-04-11T01:37:56Z

Prospects for a high field ITER device Bromberg, L.; Myer, R.C.; Cohn, D.R.; Schwartz, J.; Williams, J.E.

Theory of efficiency enhancement in CARM amplifiers by magnetic field tapering

2019-04-11T01:37:57Z

Theory of efficiency enhancement in CARM amplifiers by magnetic field tapering Chen, C.; Wurtele, J.S.

Measurement of the current density profile in the Alcator C tokamak using lithium pellets

2019-04-10T21:05:32Z

Measurement of the current density profile in the Alcator C tokamak using lithium pellets Marmar, E.S.; Terry, J.L.; Lipschultz, B.; Rice, J.E.

On the theoretical foundations of the tokamak [beta] a B /I limit

2019-04-12T20:43:49Z

On the theoretical foundations of the tokamak [beta] a B /I limit Ramos, J.J.

Measurement of suprathermal electrons in tokamaks via electron cyclotron transmission

2019-04-12T20:43:50Z

Measurement of suprathermal electrons in tokamaks via electron cyclotron transmission Kirkwood, R.K.; Hutchinson, I.H.; Luckhardt, S.C.; Squire, J.P.

Electron cyclotron heating studies of the Compact Ignition Tokamak (CIT)

2019-04-11T00:22:08Z

Electron cyclotron heating studies of the Compact Ignition Tokamak (CIT) Porkolab, M.; Bonoli, P.T.; Englade, R.; Myer, R.

Neoclassical transport of isotropic fast ions

2019-04-11T00:22:10Z

Neoclassical transport of isotropic fast ions Hsu, C.T.; Catto, P.T.; Sigmar, D.J.

Measurement of sheath potential and metal surface phenomena at the Alcator C plasma edge

2019-04-11T00:22:10Z

Measurement of sheath potential and metal surface phenomena at the Alcator C plasma edge Yang, T.F.; Wan, A.S.; Megusar, J.; Luan, G.S.

Poloidal field system analysis and scenario development for ITER

2019-04-11T00:22:11Z

Poloidal field system analysis and scenario development for ITER Schultz, J.H.; Bulmer, R.; Miller, J.

Variational methods for studying tokamak stability in the presence of a resistive wall

2019-04-09T16:21:04Z

Variational methods for studying tokamak stability in the presence of a resistive wall Haney, S.W.; Freidberg, J.P.

Neoclassical analysis of impurity transport following transition to improved particle confinement

2019-04-09T19:18:35Z

Neoclassical analysis of impurity transport following transition to improved particle confinement Wenzel, K.W.; Sigmar, D.J.

Design and R&D for 22 T central solenoid for CIT

2019-04-12T20:43:48Z

Design and R&D for 22 T central solenoid for CIT Thome, R.J.; Pillsbury, R.D.; Bobrov, E.S.; Vieira, R.; Feng, J.

Cylindrical Brillouin flow in relativistic smooth-bore magnetrons

2019-04-11T00:22:08Z

Cylindrical Brillouin flow in relativistic smooth-bore magnetrons Davidson, R.C.; Johnston, G.L.; Tsang, K.T.; Drobot, A.T.

X-ray imaging arrays for impurity transport studies in the Texas Experimental Tokamak

2019-04-12T20:43:45Z

X-ray imaging arrays for impurity transport studies in the Texas Experimental Tokamak Wenzel, K.W.; Petrasso, R.D.

Observations of field profile modifications in a Raman free electron laser

2019-04-12T20:43:46Z

Observations of field profile modifications in a Raman free electron laser Xu, K.; Bekefi, G.; Leibovitch, C.

Electron cyclotron wave propagation and absorption in the Compact Ignition Tokamak

2019-04-12T20:43:46Z

Electron cyclotron wave propagation and absorption in the Compact Ignition Tokamak Myer, R.C.; Porkolab, M.; Smith, G.R.; Kritz, A.H.

Periodic interactions of charged particles with localized fields -- the spatial standard map

2019-04-11T00:22:05Z

Periodic interactions of charged particles with localized fields -- the spatial standard map Ram, A.K.; Bers, A.; Kupfer, K.

Power balance analysis of ion Bernstein wave heating experiments in the Alcator C tokamak

2019-04-11T00:22:04Z

Power balance analysis of ion Bernstein wave heating experiments in the Alcator C tokamak Moody, J.D.; Porkolab, M.

A 35 gigaherz cyclotron autoresonance maser (CARM) amplifier

2019-04-11T00:22:06Z

A 35 gigaherz cyclotron autoresonance maser (CARM) amplifier Bekefi, G.; Rienzo, A.; Leibovitch, C.; Danly, B.G.

Atomic hydrogen density measurements in the Tara tandem mirror experiment

2019-04-12T20:43:45Z

Atomic hydrogen density measurements in the Tara tandem mirror experiment Guss, W.C.; Yao, X.Z.; Pocs, L.; Mahon, R.; Casey, J.; Horne, S.; Lane, B.; Post, R.S.; Torti, R.P.

Gyrotron powered standing wave electromagnetic wiggler experiment

2019-04-12T20:43:45Z

Gyrotron powered standing wave electromagnetic wiggler experiment Chu, T.S.; Danly, B.G.; Temkin, R.

Tunable micro-wigglers for free electron lasers

2019-04-12T20:43:44Z

Tunable micro-wigglers for free electron lasers Chen, S.C.; Bekefi, G.; Cecca, S.; Temkin, R.

Tokamak plasmas: a paradigm for coronal equilibrium and disequilibrium

2019-04-12T20:43:44Z

Tokamak plasmas: a paradigm for coronal equilibrium and disequilibrium Petrasso, Richard

Comparison of two ICCS conductors for MHD applications

2019-04-11T00:22:01Z

Comparison of two ICCS conductors for MHD applications Hale, J.R.; Marston, P.G.; Dawson, A.M.

Effect of local shear on drift fluctuation driven transport in tokamaks

2019-04-11T00:22:04Z

Effect of local shear on drift fluctuation driven transport in tokamaks Kesner, J.

RF assisted ohmic current ramp up in the Compact Ignition Tokamak

2019-04-11T00:22:03Z

RF assisted ohmic current ramp up in the Compact Ignition Tokamak Bonoli, P.T.; Porkolab, M.

Stability issues in the Tara tandem mirror experiment

2019-04-12T20:43:42Z

Stability issues in the Tara tandem mirror experiment Post, R.S.; Brau, K.; Casey, J.; Coleman, J.; Gerver, M.; Golovato, S.N.

Whistler instability in an ECRH, mirror-confined plasma

2019-04-12T20:43:41Z

Whistler instability in an ECRH, mirror-confined plasma Garner, R.C.; Mauel, M.E.; Hokin, S.A.; Post, R.S.; Smatlak, D.L.

Advanced superconducting MHD magnet design for a retrofit power plant

2019-04-12T20:43:42Z

Advanced superconducting MHD magnet design for a retrofit power plant Marston, P.G.; Hale, J.R.; Dawson, A.M.

Waves and instabilities in nonneutral plasmas

2019-04-11T00:21:58Z

Waves and instabilities in nonneutral plasmas Davidson, Ronald

A high-power, 600um wavelength free-electron laser

2019-04-11T00:21:59Z

A high-power, 600um wavelength free-electron laser Kirkpatrick, D.A.; Bekefi, G.; Rienzo, A.C.; Freund, H.P.; Ganguly, A.K.

The production and maintenance of high epsilon beta (sub p) tokamak plasmas by means of RF current

2019-04-12T20:43:40Z

The production and maintenance of high epsilon beta (sub p) tokamak plasmas by means of RF current Luckhardt, S.; Chen, K.I.; Kesner, J.; Kirkwood, R.; Lane, B.; Porkolab, M.

Conditions for absolute instability in the cyclotron resonance maser

2019-04-12T20:43:40Z

Conditions for absolute instability in the cyclotron resonance maser Davies, J.A.

Stabilization of the cyclotron autoresonance maser (CARM) instability by axial momentum spread

2019-04-12T20:43:39Z

Stabilization of the cyclotron autoresonance maser (CARM) instability by axial momentum spread Davidson, R.C.; Yoon, P.H.

Performance limits of high field tokamak reactors

2019-04-09T19:10:22Z

Performance limits of high field tokamak reactors Schwartz, J.; Bromberg, L.; Cohn, D.R.; Williams, J.E.

Gamma-ray diagnostic for the compact ignition tokamak

2019-04-11T00:21:54Z

Gamma-ray diagnostic for the compact ignition tokamak Petrasso, R.D.; Fiore, C.L.; Li, C.K.

Nonlinear bound on unstable field energy in relativistic electron beams and plasmas

2019-04-11T00:21:58Z

Nonlinear bound on unstable field energy in relativistic electron beams and plasmas Davidson, R.C.; Yoon, P.H.

H alpha fluorescence diagnostic on the Tara tandem mirror experiment

2019-04-12T20:43:37Z

H alpha fluorescence diagnostic on the Tara tandem mirror experiment Guss, W.C.; Yao, X.Z.; Pocs, L.; Mahon, R.; Casey, J.; Post, R.S.

On dissipative mode-coupling in ICRF minority heating

2019-04-12T20:43:37Z

On dissipative mode-coupling in ICRF minority heating Fuchs, V.; Bers, A.

Stability of plasmas sustained by ICRF in the central cell of the Tara tandem mirror

2019-04-09T17:50:43Z

Stability of plasmas sustained by ICRF in the central cell of the Tara tandem mirror Golovato, S.N.; Brau, K.; Casey, J.; Gerver, M.J.; Horne, S.; Irby, J.; Kesner, J.; Lane, B.; Machuzak, J.; Myer, R.; Post, R.S.; Sevillano, E.; Wang, L.

Suppression of feedback oscillations in free electron lasers

2019-04-10T17:36:42Z

Suppression of feedback oscillations in free electron lasers Fajans, J.; Wurtele, J.S.

Neutral beam heating considerations for CIT.

2019-04-11T00:21:52Z

Neutral beam heating considerations for CIT. Wei, J.; Bromberg, L.; Myer, R.C.; Cohn, D.R.

Depletion and diffraction of an electromagnetic wiggler field during the free electron laser interaction

2019-04-11T00:21:53Z

Depletion and diffraction of an electromagnetic wiggler field during the free electron laser interaction Similon, P.L.; Wurtele, J.S.

Plasma production and heating by ICRF in the central cell of the Tara tandem mirror

2019-04-11T00:21:53Z

Plasma production and heating by ICRF in the central cell of the Tara tandem mirror Golovato, S.N.; Brau, K.; Casey, J.; Coleman, J.; Gerver, M.J.; Guss, W.; Hallock, G.; Horne, S.; Irby, J.; Kumazawa, R.; Kesner, J.; Lane, B.; Machuzak, J.; Moran, T.; Myer, R.; Post, R.S.; Sevillano, E.; Smith, D.K.; Sullivan, J.D.; Torti, R.; Wang, L.

Observation of trapped particle modes in a tandem mirror

2019-04-12T20:43:35Z

Observation of trapped particle modes in a tandem mirror Gerver, M.J.; Golovato, S.N.; Irby, J.H.; Kesner, J.

Operation of an E parallel B end loss ion spectrometer on the Tara tandem mirror

2019-04-12T20:43:28Z

Operation of an E parallel B end loss ion spectrometer on the Tara tandem mirror Casey, J.A.; Horne, S.F.; Irby, J.H.; Post, R.S.; Sevillano, E.; Foote, J.H.

X-ray observations between 10 and 150 KeV from the Alcator C tokamak

2019-04-10T17:36:36Z

X-ray observations between 10 and 150 KeV from the Alcator C tokamak Rice, J.E.; Chamberlain, K.L.

Comments on Shimomura-Odajima scaling

2019-04-10T17:36:39Z

Comments on Shimomura-Odajima scaling Sigmar, D.J.; Hsu, H.S.

X-ray response of silicon surface barrier diodes at 8 and 17.5 keV: evidence that the x-ray sensitive depth is not generally the depletion depth

2019-04-10T17:36:38Z

X-ray response of silicon surface barrier diodes at 8 and 17.5 keV: evidence that the x-ray sensitive depth is not generally the depletion depth Wenzel, K.W.; Petrasso, R.D.

Effect of scattering parameters on the detection of the alpha particle distribution function for co2 laser or millimeter incident radiation

2019-04-12T20:43:26Z

Effect of scattering parameters on the detection of the alpha particle distribution function for co2 laser or millimeter incident radiation Vahala, L.; Vahala, G.; Sigmar, D.

Effects of electron prebunching on the radiation growth rate of a collective (Raman) free electron laser amplifier

2019-04-12T20:43:27Z

Effects of electron prebunching on the radiation growth rate of a collective (Raman) free electron laser amplifier Leibovitch, C.; Xu, K.; Bekefi, G.

A kinetic theory of ion collection by probing objects in flowing strongly magnetized plasmas

2019-04-12T20:43:27Z

A kinetic theory of ion collection by probing objects in flowing strongly magnetized plasmas Chung, K; Hutchinson, I.H.

Terminated whistler emissions in the magnetosphere

2019-04-10T17:36:29Z

Terminated whistler emissions in the magnetosphere Miller, R.H.; Molvig, K.

Resonant operation of the cross-field free electron laser: kinetic and fluid equilibria

2019-04-10T17:36:29Z

Resonant operation of the cross-field free electron laser: kinetic and fluid equilibria Johnston, G.L.; Hartemann, F.; Davidson, R.C.; Bekefi, G.

Ion collection by probes in strong magnetic fields with plasma flow

2019-04-10T17:36:28Z

Ion collection by probes in strong magnetic fields with plasma flow Hutchinson, I.H.

Analysis and measurements of permanent magnet and "bifilar" helical wigglers

2019-04-10T17:36:28Z

Analysis and measurements of permanent magnet and "bifilar" helical wigglers Ashkenazy, J.; Bekefi, G.

Possible high-frequency cavity and waveguide applications of high temperature superconductors

2019-04-12T20:43:23Z

Possible high-frequency cavity and waveguide applications of high temperature superconductors Cohn, D.R.; Bromberg, L.; Halverson, W.; Lax, B.; Woskov, P.

Quasi-optical gyrotron with arbitrary beam injection angle

2019-04-12T20:43:23Z

Quasi-optical gyrotron with arbitrary beam injection angle Wang, C.Y.; Kreischer, K.E.; Temkin, R.J.

Absolute instabilities and self-sustained oscillations in the wake of circular cylindars

2019-04-10T17:36:26Z

Absolute instabilities and self-sustained oscillations in the wake of circular cylindars Triantafyllou, G.S.; Kupfer, K.; Bers, A.

Poloidal field system analysis and scenario development for the TIBER/ITER

2019-04-09T15:19:07Z

Poloidal field system analysis and scenario development for the TIBER/ITER Schultz, J.H.

Microwave plasma diagnostics

2019-04-10T17:36:27Z

Microwave plasma diagnostics Meuth, H.; Sevillano, E.

Time-of-flight analyzer for ion endloss of a mirror plasma

2019-04-10T17:36:22Z

Time-of-flight analyzer for ion endloss of a mirror plasma Petty, C.C.; Smith, D.K.; Smatlak, D.L.

Engineering features of the Alcator C-Mod tokamak

2019-04-12T20:43:23Z

Engineering features of the Alcator C-Mod tokamak Becker, H.; Besen, M.; Childs, R.; Diatchenko, N.; Fertl, K.; Gwinn, D.; Humphries, D.; Hutchinson, I.; Lipschultz, B.; Montgomery, D.B.; Pierce, N.; Pillsbury, R.; Schultz, J.H.; Vieira, R.; Wolfe, S.

Experimental study of the hot electron plasma equilibrium in the Constance B mirror

2019-04-10T16:58:02Z

Experimental study of the hot electron plasma equilibrium in the Constance B mirror Chen, X.; Lane, B.G.; Smatlak, D.L.; Post, R.S.; Hokin, S.A.

Self-consistent simulation of cyclotron autoresonance maser amplifiers

2019-04-10T17:36:21Z

Self-consistent simulation of cyclotron autoresonance maser amplifiers Pendergast, K.D.; Danly, B.G.; Temkin, R.J.; Wurtele, J.S.

Access to the second stability region in a high shear, low aspect ratio tokamak

2019-04-10T17:36:22Z

Access to the second stability region in a high shear, low aspect ratio tokamak Gerver, M.J.; Kesner, J.; Ramos, J.J.

Stabilization of sawteeth by lower hybrid waves in the Alcator C tokamak

2019-04-12T20:43:21Z

Stabilization of sawteeth by lower hybrid waves in the Alcator C tokamak Knowlton, S.; Porkolab, M.; Takase, Y.

A theory of fast wave absorption, transmission and reflection in the ion cyclotron range of frequency

2019-04-12T20:43:21Z

A theory of fast wave absorption, transmission and reflection in the ion cyclotron range of frequency Fuchs, V.; Francis, G.; Ram, A.K.; Bers, A.; Gauthier, A.

Three-dimensional equilibria in DRAKONs

2019-04-12T20:43:22Z

Three-dimensional equilibria in DRAKONs Lau, Y.T.

Numerical modeling of lower hybrid RF heating and current drive experiments in the Alcator C tokamak

2019-04-12T20:43:22Z

Numerical modeling of lower hybrid RF heating and current drive experiments in the Alcator C tokamak Bonoli, P.T.; Porkolab, M.; Takase, Y.; Knowlton, S.

Pulse shapes for absolute and convective free electron laser instabilities

2019-04-09T16:37:13Z

Pulse shapes for absolute and convective free electron laser instabilities Davies, J.A.; Davidson, R.C.; Johnston, G.L.

Theory of global interchange modes in shaped tokamaks with small central shear

2019-04-10T17:36:21Z

Theory of global interchange modes in shaped tokamaks with small central shear Ramos, J.J.

Magnetic probes for small signal detection in a large background field

2019-04-10T17:36:20Z

Magnetic probes for small signal detection in a large background field Chen, X.

A pseudo-tomographic fitting algorithm for density profile resconstruction from a sparse 1-D interferometer array

2019-04-12T20:43:19Z

A pseudo-tomographic fitting algorithm for density profile resconstruction from a sparse 1-D interferometer array Casey, J.A.; Sevillano, E.; Irby, J.H.; Lane, B.G.

Generation of short pulses of coherent electromagnetic radiation in a free electron laser amplifier

2019-04-12T20:43:20Z

Generation of short pulses of coherent electromagnetic radiation in a free electron laser amplifier Hartemann, F.; Xu, K.; Bekefi, G.

Microwave measurement of the mass of frozen hydrogen pellets

2019-04-12T20:43:21Z

Microwave measurement of the mass of frozen hydrogen pellets Talanker, V.; Greenwald, M.

The application of the finite element library twodepep for the numerical solution of the relativistic fokker-planck equation

2019-04-12T20:43:19Z

The application of the finite element library twodepep for the numerical solution of the relativistic fokker-planck equation Shoucri, M.; Fuchs, V.; Bers, A.

Desirability of approaches to achieving high beta

2019-04-12T20:43:18Z

Desirability of approaches to achieving high beta Haney, S.W.; Freidberg, J.P.

Ion Bernstein wave heating and improved confinement on the Alcator C tokamak

2019-04-12T20:43:18Z

Ion Bernstein wave heating and improved confinement on the Alcator C tokamak Moody, J.D.; Porkolab, M.; Fiore, C.L.; Dermott, F.S.; Takase, Y.

Particle transport simulation of density behavior during lower-hybrid current drive experiments on the Versator II tokamak

2019-04-12T20:43:19Z

Particle transport simulation of density behavior during lower-hybrid current drive experiments on the Versator II tokamak Chen, K.I.; Luckhardt, S.C.; Mayberry, M.J.; Porkolab, M.

Experimental studies of divertor stabilization in an axisymmetric tandem mirror

2019-04-12T20:43:19Z

Experimental studies of divertor stabilization in an axisymmetric tandem mirror Casey, J.A.; Lane, B.G.; Irby, J.H.; Brau, K.L.; Golovato, S.N.; Guss, W.C.; Kesner, J.; Post, R.S.; Sevillano, E.; Zielinski, C.J.

Single mode operation of a high power, step tunable gyrotron

2019-04-10T17:36:17Z

Single mode operation of a high power, step tunable gyrotron Kreischer, K.E.; Temkin, R.J.

Tokamak reactor concepts using high temperature, high field superconductors

2019-04-10T17:36:17Z

Tokamak reactor concepts using high temperature, high field superconductors Cohn, D.R.; Schwartz, J.; Bromberg, L.; Williams, J.E.

Wave profile modification (optical guiding) induced by the free electron laser interaction

2019-04-10T17:36:20Z

Wave profile modification (optical guiding) induced by the free electron laser interaction Hartmann, S.; Xu, K.; Bekefi, G.; Wurtele, J.S.; Fajans, J.

A /->/k-space integral equation for describing propagation through a strongly inhomogeneous plasma density profile

2019-04-12T20:43:17Z

A /->/k-space integral equation for describing propagation through a strongly inhomogeneous plasma density profile Myer, R.C.; Fried, B.D.

Experimental study of nonlinear m=1 modes in the Tara tandem mirror

2019-04-12T20:43:16Z

Experimental study of nonlinear m=1 modes in the Tara tandem mirror Irby, J.H.; Lane, B.G.; Casey, J.A.; Brau, K.; Golovato, S.N.; Guss, W.C.; Horne, S.F.; Kesner, J.; Post, R.S.; Sevillano, E.; Sullivan, J.D.; Smith, D.K.

Permanent magnet helical wiggler for free electron laser and cyclotron maser applications

2019-04-12T20:43:17Z

Permanent magnet helical wiggler for free electron laser and cyclotron maser applications Bekefi, G.; Ashkenazy, J.

MHD clump instability

2019-04-09T16:03:11Z

MHD clump instability Tetreault, D.

Steady state MHD clump turbulence

2019-04-10T17:36:15Z

Steady state MHD clump turbulence Tetreault, D.

Cusp stabilized mirror based neutron source

2019-04-12T20:43:16Z

Cusp stabilized mirror based neutron source Kesner, J.; Horne, S.F.

The cusp map in the complex-frequency plane for absolute instabilities

2019-04-09T17:04:05Z

The cusp map in the complex-frequency plane for absolute instabilities Kupfer, K.; Bers, A.; Ram, A.K.

Microwave radiation from a tuneable circular free electron laser

2019-04-12T20:43:16Z

Microwave radiation from a tuneable circular free electron laser Hartemann, F.; Bekefi, G.

An acousto-optic spectrum analyzer for plasma diagnostics

2019-04-10T17:36:14Z

An acousto-optic spectrum analyzer for plasma diagnostics Irby, J.H.; Beals, D.

Temporal evolution of beam emittance from a field emission electron

2019-04-10T17:36:15Z

Temporal evolution of beam emittance from a field emission electron Bekefi, G.; Hartemann, F.; Kirkpatrick, D.A.

Experimental observation of the hot electron equilibrium in a minimum-B mirror plasma

2019-04-11T00:21:45Z

Experimental observation of the hot electron equilibrium in a minimum-B mirror plasma Smatlak, D.L.; Chen, X.; Lane, B.G.; Hokin, S.A.; Post, R.S.

Particle confinement improvement during 2.45 GHz lower hybrid current drive experiments

2019-04-12T20:43:14Z

Particle confinement improvement during 2.45 GHz lower hybrid current drive experiments Mayberry, M.J.; Chen, K.I.; Luckhardt, S.C.; Porkolab, M.

Free-electron lasers and their application to biomedicine

2019-04-12T20:43:15Z

Free-electron lasers and their application to biomedicine Danly, B.D.; Temkin, R.J.; Bekefi, G.

Review of the magnetic fusion program by the 1986 ERAB fusion panel

2019-04-12T20:43:15Z

Review of the magnetic fusion program by the 1986 ERAB fusion panel Davidson, R.C.

A Fluid theory of ion collection by probes in strong magnetic fields with plasma flow

2019-04-10T17:36:13Z

A Fluid theory of ion collection by probes in strong magnetic fields with plasma flow Hutchinson, I.

Kinetic equilibrium and stability properties of high-current betatrons

2019-04-10T17:36:13Z

Kinetic equilibrium and stability properties of high-current betatrons Petillo, J.J.; Davidson, R.C.

RF current generation by lower hybrid slow waves in the presence of fusion generated alpha-particles in the reactor regime

2019-04-10T17:36:14Z

RF current generation by lower hybrid slow waves in the presence of fusion generated alpha-particles in the reactor regime Bonoli, P.; Porkolab, M.

Extraordinary mode absorption at the electron cyclotron harmonic frequencies as a tokamak electron temperature diagnostic

2019-04-12T20:43:14Z

Extraordinary mode absorption at the electron cyclotron harmonic frequencies as a tokamak electron temperature diagnostic Pachtman, A.; Wolfe, S.M.; Hutchinson, I.H.

Diagnosis of mildly relativistic electron velocity distributions by electron cyclotron emission in Alcator C

2019-04-12T20:43:14Z

Diagnosis of mildly relativistic electron velocity distributions by electron cyclotron emission in Alcator C Hutchinson, I.; Kato, K.

A study of directly launched ion bernstein waves in a tokamak

2019-04-12T20:43:14Z

A study of directly launched ion bernstein waves in a tokamak Takase, Y.; Moody, J.D.; Fiore, C.L.; Dermott, F.S.; Porkolab, M.; Squire, J.

Stabilization of MHD modes in an axisymmetric plasma column through the use of a magnetic divertor

2019-04-10T17:36:10Z

Stabilization of MHD modes in an axisymmetric plasma column through the use of a magnetic divertor Kesner, J.; Lane, B.; Post, R.S.

Narrow bandwidth emission from a mirrorless, far infrared, super 13CHsub3F laser

2019-04-10T17:36:12Z

Narrow bandwidth emission from a mirrorless, far infrared, super 13CHsub3F laser Evangelides, S.G.; Carson, L.; Danly, B.G.; Temkin, R.J.

Influence of untrapped electrons on the sideband instability in a helical wiggler free electron laser

2019-04-10T17:36:12Z

Influence of untrapped electrons on the sideband instability in a helical wiggler free electron laser Davidson, R.C.; Wurtele, J.S.

Plasma current ramp-up and ohmic-heating transformer recharging experiments using lower-hybrid waves on the Alcator C tokamak

2019-04-12T20:43:12Z

Plasma current ramp-up and ohmic-heating transformer recharging experiments using lower-hybrid waves on the Alcator C tokamak Takase, Y.; Knowlton, S.; Porkolab, M.

Effect of electron beam temperature on the gain of a collective free electron laser

2019-04-12T20:43:13Z

Effect of electron beam temperature on the gain of a collective free electron laser Fajans, J.; Bekefi, G.

Neoclassical flux-friction relations for arbitrary closed-end plasmas

2019-04-12T20:43:13Z

Neoclassical flux-friction relations for arbitrary closed-end plasmas Lau, Y.T.

Relativistic nonneutral electron flow in a planar triode

2019-04-12T20:42:50Z

Relativistic nonneutral electron flow in a planar triode Chan, Hei; Davidson, R.C.; Nguyen, K.T.; Uhm, H.S.

Radio profiles of ground state transitions of helium-like argon from the Alcator C tokamak

2019-04-12T20:42:51Z

Radio profiles of ground state transitions of helium-like argon from the Alcator C tokamak Rice, J.; Marmar, E.; Kallne, E.; Kallne, J.

Generation of electromagnetic radiation from a drifting and rotating electron ring in a rippled magnetic field

2019-04-12T20:43:11Z

Generation of electromagnetic radiation from a drifting and rotating electron ring in a rippled magnetic field Yin, Y; Ying, R; Bekefi, G.

Cerenkov-electrooptic shutter--a subnanosecond intense, relativistic electron beam diagnostic

2019-04-12T20:42:50Z

Cerenkov-electrooptic shutter--a subnanosecond intense, relativistic electron beam diagnostic Hartmann, F.; Bekefi, G.

Fusion reactions of polarized deuterons

2019-04-09T15:27:36Z

Fusion reactions of polarized deuterons Zhang, J.S.; Liu, K.F.; Shuy, G.W.

Closed analytical model of the electron whistler and cyclotron maser instabilities in relativistic plasma with arbitrary energy anisotropy

2019-04-12T20:43:11Z

Closed analytical model of the electron whistler and cyclotron maser instabilities in relativistic plasma with arbitrary energy anisotropy Yoon, P.H.; Davidson, R.C.

Free electron lasers with electromagnetic standing wave wigglers

2019-04-10T17:36:07Z

Free electron lasers with electromagnetic standing wave wigglers Tran, T.M.; Danly, B.G.; Wurtele, J.S.

Sliding joint and bond development program for the Alcator C-Mod toroidal field coils

2019-04-10T17:36:06Z

Sliding joint and bond development program for the Alcator C-Mod toroidal field coils Montgomery, D.B.; Schultz, J.H.; Beck, W.K.; Becker, H.D.; Besen, M.M.; Gwinn, D.A.; Pierce, N.Y.; Pillsbury, R.D.

Review of MARFE phemonema in tokamaks

2019-04-12T20:42:49Z

Review of MARFE phemonema in tokamaks Lipschultz, B.

Compton and Raman free electron laser stability properties for a warm electron beam propagating through a helical magnetic wiggler

2019-04-12T20:42:50Z

Compton and Raman free electron laser stability properties for a warm electron beam propagating through a helical magnetic wiggler Davies, J.A.; Davidson, R.C.; Johnston, G.L.

Efficiency of RF current drive in the presence of fast particle losses

2019-04-12T20:42:48Z

Efficiency of RF current drive in the presence of fast particle losses Luckhardt, S.C.

Precision measurements of the wavelengths of emission lines of Mg-like and Ma-like Kr in Alcator C plasmas

2019-04-12T20:42:49Z

Precision measurements of the wavelengths of emission lines of Mg-like and Ma-like Kr in Alcator C plasmas Kondo, K.; Terry, J.L.; Rice, J.E.; Marmar, E.S.

Energy confinement studies of lower hybrid current driven plasmas in the Alcator C tokamak

2019-04-11T00:21:45Z

Energy confinement studies of lower hybrid current driven plasmas in the Alcator C tokamak Takase, Y.; Bonoli, P.; Knowlton, S.; Porkolab, M.; Texter, S.; Fiore, C.; Cool, S.; Dermott, S.; Terry, J.

Redeposition of SiC-coated graphite limiter in Alcator C

2019-04-11T00:21:44Z

Redeposition of SiC-coated graphite limiter in Alcator C Megusar, J.; Yang, T.F.; Martin, J.R.; Wan, A.S.

Exact analytical model of the classical Weibel instability in relativistic anisotropic plasma

2019-04-10T17:36:05Z

Exact analytical model of the classical Weibel instability in relativistic anisotropic plasma Yoon, P.H.; Davidson, R.C.

Kinetic analysis of the sideband instability in a helical wiggler free laser for electrons trapped near the bottom of the ponderomotive potential

2019-04-10T07:18:29Z

Kinetic analysis of the sideband instability in a helical wiggler free laser for electrons trapped near the bottom of the ponderomotive potential Davidson, R.C.; Wurtele, J.S.; Aamodt, R.E.

Single particle analysis of the free electron laser sideband instability for primary electromagnetic wave with constant phase and slowly varying phase

2019-04-12T20:42:46Z

Single particle analysis of the free electron laser sideband instability for primary electromagnetic wave with constant phase and slowly varying phase Davidson, R.; Wurtele, J.

RF-induced electron endloss from an ECRH mirror plasma

2019-04-12T20:42:47Z

RF-induced electron endloss from an ECRH mirror plasma Hokin, S.; Garner, R.C.; Post, R.S.; Smatlak, D.L.

Electron microinstabilities in an RF-heated, mirror-confined plasma

2019-04-12T20:42:45Z

Electron microinstabilities in an RF-heated, mirror-confined plasma Garner, R.C.; Mauel, M.E.; Hokin, S.A.; Post, R.S.; Smatlak, D.L.

Observations of centrally peaked impurity profiles following pellet injection in the Alcator C tokamak

2019-04-11T00:21:40Z

Observations of centrally peaked impurity profiles following pellet injection in the Alcator C tokamak Petrasso, R.D.; Sigmar, D.J.; Wenzel, K.W.; Hopf, J.E.; Greenwald, M.; Terry, J.L.; Parker, J.

Improved plasma startup in the Tara central cell

2019-04-11T00:21:40Z

Improved plasma startup in the Tara central cell Post, R.S.; Brau, K.; Golovato, S.; Sevillano, E.; Smith, D.K.; Guss, W.; Irby, J.; Myer, R.; Sullivan, J.

A high-power radio-frequency plasma source

2019-04-12T20:42:44Z

A high-power radio-frequency plasma source Petty, C.C.; Smith, D.K.

Convective influx of plasma and beams in tokamaks with asymmetric ripple

2019-04-12T20:42:45Z

Convective influx of plasma and beams in tokamaks with asymmetric ripple Yang, T.F.; Wang, P.W.

On the linear theory of circular free electron lasers

2019-04-12T20:42:44Z

On the linear theory of circular free electron lasers Saito, H.; Wurtele, J.S.

Requirements for ohmic ignition

2019-04-12T20:42:45Z

Requirements for ohmic ignition Hutchinson, I.H.

Free-electron laser radiation induced by a periodic dielectric medium

2019-04-11T07:37:13Z

Free-electron laser radiation induced by a periodic dielectric medium Bekefi, G.; Wurtele, J.S.; Deutch, I.H.

Gyrotron powered electromagnetic wigglers for free electron lasers

2019-04-10T21:06:35Z

Gyrotron powered electromagnetic wigglers for free electron lasers Danly, B.G.; Bekefi, G.; Davidson, R.C.; Temkin, R.J.; Tran, T.M.; Wurtele, J.S.

Nonlinear power saturation and phase (wave refractive index) in the collective free electron laser

2019-04-12T20:42:44Z

Nonlinear power saturation and phase (wave refractive index) in the collective free electron laser Fajans, J.; Wurtele, J.S.; Bekefi, G.; Knowles, D.S.; Xu, K.

Anomalous Doppler instability during lower hybrid current drive

2019-04-12T20:42:43Z

Anomalous Doppler instability during lower hybrid current drive Luckhardt, S.C.; Bers, A.; Fuchs, V.; Shoucri, M.

A new look at density limits in tokamaks

2019-04-12T20:42:43Z

A new look at density limits in tokamaks Greenwald, M.; Terry, J.; Wolfe, S.; Ejima, S.; Bell, M.; Kaye, S.; Neilson, G.H.

Measurements of amplification and phase shift (wave refractive index) in a free-electron laser

2019-04-11T07:37:11Z

Measurements of amplification and phase shift (wave refractive index) in a free-electron laser Fajans, J.; Bekefi, G.

Double parallel-plate electrostatic analyzer for Tara endloss studies

2019-04-11T07:37:12Z

Double parallel-plate electrostatic analyzer for Tara endloss studies Sullivan, J.; Casey, J.A.; Irby, J.H.; Smith, D.K.; Sevillano, E.

Thomson scattering in the Tara tandem mirror central cell

2019-04-11T07:37:12Z

Thomson scattering in the Tara tandem mirror central cell Casey, J.A.; Irby, J.H.

Development of gyrotrons for plasma diagnostics

2019-04-11T07:37:11Z

Development of gyrotrons for plasma diagnostics Woskoboinikow, P.

Impurity generation during ICRF heating experiments on Alcator C

2019-04-12T20:42:42Z

Impurity generation during ICRF heating experiments on Alcator C Manning, H.L.; Terry, J.L.; Lipschultz, B.; Bombard, B.; Blackwell, B.D.; Fiore, C.L.; Foord, M.E.; Marmar, E.S.; Moody, J.D.; Parker, R.R.; Porkolab, M.; Rice, J.E.

Simulation model for hybrid current drive

2019-04-11T04:44:41Z

Simulation model for hybrid current drive Englade, R.

Variational quadratic form for low frequency electromagnetic perturbations: (II) application to tandem mirrors

2019-04-09T15:52:04Z

Variational quadratic form for low frequency electromagnetic perturbations: (II) application to tandem mirrors Berk, H.L.; Lane, B.

Energy confinement of the high energy tail electrons during lower hybrid current drive on the Alcator C tokamak

2019-04-10T20:57:45Z

Energy confinement of the high energy tail electrons during lower hybrid current drive on the Alcator C tokamak Textor, S.; Bonoli, P.; Knowlton, S.; Porkolab, M.; Takase, Y.

Lower hydrid wave launching and antenna design

2019-04-12T20:42:41Z

Lower hydrid wave launching and antenna design Knowlton, S.F.; Porkolab, M.

Non-destructive gyrotron cold cavity Q measurements

2019-04-12T20:42:41Z

Non-destructive gyrotron cold cavity Q measurements Woskoboinikow, P.; Mulligan, W.J.

High energy x-ray measurements during lower hybrid current drive on the Alcator C tokamak

2019-04-12T20:42:42Z

High energy x-ray measurements during lower hybrid current drive on the Alcator C tokamak Textor, S.; Knowlton, S.; Porkolab, M.; Takase, Y.

Impurity sources during lower-hybrid heating on Alcator C

2019-04-11T04:44:25Z

Impurity sources during lower-hybrid heating on Alcator C Lipschultz, B.; Bombard, B.; Manning, H.L.; Terry, J.L.; Knowlton, S.; Marmar, E.S.; Porkolab, M.; Rice, J.; Takase, Y.; Texter, S.; Wan, A.

Energy confinement of lower hybrid current driven tokamak plasmas

2019-04-11T04:44:29Z

Energy confinement of lower hybrid current driven tokamak plasmas Knowlton, S.; Porkolab, M.; Takase, Y.; Texter, S.; Bonoli, P.; Fiore, C.; Cool, S.; Dermott, F.S.; Terry, J.L.

Analytic treatment of linearized self-consistent theory of a gyromonotron...

2019-04-11T04:44:29Z

Analytic treatment of linearized self-consistent theory of a gyromonotron... Saito, H.

A gyrotron with minimum Q cavity

2019-04-12T20:42:40Z

A gyrotron with minimum Q cavity Saito, H.

Design and performance of compact vacuum-compatible submillimeter viewing dumps

2019-04-12T20:42:41Z

Design and performance of compact vacuum-compatible submillimeter viewing dumps Kato, K.; Hutchinson, I.H.

Observations of centrally peaked impurity profiles in the Alcator C tokamak following pellet injection

2019-04-11T04:44:12Z

Observations of centrally peaked impurity profiles in the Alcator C tokamak following pellet injection Petrasso, R.D.; Wenzel, K.W.; Hopf, J.E.; Sigmar, D.J.; Greenwald, M.; Terry, J.L.; Parker, J.

JANUS, a bi-directional, multi-functional plasma diagnostic

2019-04-11T04:44:23Z

JANUS, a bi-directional, multi-functional plasma diagnostic Wan, A.S.; Yang, T.F.; Lipschultz, B.; Bombard, B.

DENSEPACK: an array of Langmuir probes in the limiter shadow plasma of the Alcator C tokamak fusion experiment

2019-04-10T16:54:24Z

DENSEPACK: an array of Langmuir probes in the limiter shadow plasma of the Alcator C tokamak fusion experiment Bombard, B.; Lipschultz, B.

Poloidal asymmetries in the scrapeoff layer of Alcator C

2019-04-11T04:44:14Z

Poloidal asymmetries in the scrapeoff layer of Alcator C Bombard, B.; Lipschultz, B.

Influence of intense equilibrium self fields on the cyclotron maser instability in high-current gyrotrons

2019-04-12T20:42:40Z

Influence of intense equilibrium self fields on the cyclotron maser instability in high-current gyrotrons Uhm, H.; Davidson, R.C.

Advantages of high field tokamaks for fusion reactor development

2019-04-12T20:42:40Z

Advantages of high field tokamaks for fusion reactor development Cohn, D.R.; Bromberg, L.

Theory of harmonic gyrotwystron

2019-04-11T04:44:41Z

Theory of harmonic gyrotwystron Tran, T.M.; Kreischer, K.E.; Temkin, R.J.

m = 1, n = 1 oscillations following the injection of a fuel pellet on the Alcator C tokamak

2019-04-12T20:42:39Z

m = 1, n = 1 oscillations following the injection of a fuel pellet on the Alcator C tokamak Parker, J.; Greenwald, M.; Petrasso, R.; Granetz, R.; Gomez, C.

Precision measurement of the 1S lamb shift on hydrogen-like argon

2019-04-12T20:42:37Z

Precision measurement of the 1S lamb shift on hydrogen-like argon Marmar, E.S.; Rice, J.E.; Kallne, E.; Kallne, J.

Observation of charge-transfer population of high n levels in AR +16 from neutral hydrogen in the ground and excited states in a tokamak

2019-04-12T20:42:38Z

Observation of charge-transfer population of high n levels in AR +16 from neutral hydrogen in the ground and excited states in a tokamak Rice, J.E.; Marmar, E.S.; Terry, J.L.; Kallne, E.

Non-thermal electron velocity distribution measured by electron cyclotron emission in Alcator C tokamak

2019-04-12T20:42:39Z

Non-thermal electron velocity distribution measured by electron cyclotron emission in Alcator C tokamak Kato, K.; Hutchinson, I.H.

Turbulent stabilization of the tearing mode in tokamak plasmas

2019-04-12T20:42:39Z

Turbulent stabilization of the tearing mode in tokamak plasmas Esarey, E.; Friedberg, J.P.; Molvig, K.; Beasley, C.O.; Rij, W.I.

Effect of pellet fueling on energy transport in ohmically heated Alcator C plasmas

2019-04-11T04:44:40Z

Effect of pellet fueling on energy transport in ohmically heated Alcator C plasmas Wolfe, S.M.; Greenwald, M.; Gandy, R.; Granetz, R.; Gomez, C.; Gwinn, D.; Lipschultz, B.; Cool, S.; Marmar, E.; Parker, J.; Parker, R.R.; Rice, J.

Sensitivity of energy margin and cost figures of internally cooled cabled superconductors (ICCS) to parametric variations in conductor design

2019-04-11T04:44:40Z

Sensitivity of energy margin and cost figures of internally cooled cabled superconductors (ICCS) to parametric variations in conductor design Schultz, J.H.; Minervini, J.V.

Analytical model for the perpendicular temperature enhancement in lower-hybrid current drive

2019-04-11T04:44:38Z

Analytical model for the perpendicular temperature enhancement in lower-hybrid current drive Hizanidis, K.; Bers, A.; Fuchs, V.; Cairns, R.A.

Electric probes in plasmas

2019-04-10T16:28:27Z

Electric probes in plasmas Lipschultz, B.; Hutchinson, I.; Bombard, B.; Wan, A.

Ripple stabilized high beta plasma with conducting wall in a simple mirror

2019-04-12T20:42:37Z

Ripple stabilized high beta plasma with conducting wall in a simple mirror Li, X.Z.; Kesner, J.; Destro, L.

Trapped electron stochasticity by frequency-modulated waves

2019-04-11T04:44:37Z

Trapped electron stochasticity by frequency-modulated waves Ram, A.K.; Hizanidis, K.; Bers, A.

One-dimensional model for lower hybrid current drive including perpendicular dynamics

2019-04-11T04:44:36Z

One-dimensional model for lower hybrid current drive including perpendicular dynamics Fuchs, V.; Cairns, R.A.; Shoucri, M.M.; Hizanidis, K.; Bers, A.

Off axis electron orbits in realistic helical wigglers for free-electron lasers applications

2019-04-11T04:44:37Z

Off axis electron orbits in realistic helical wigglers for free-electron lasers applications Fajans, J.; Kirkpatrick, D.A.; Bekefi, G.

Prospects for high power gyrotrons

2019-04-12T20:42:35Z

Prospects for high power gyrotrons Kreischer, K.; Danly, B.G.; Saito, H.; Schutkeker, J.B.; Temkin, R.J.; Tran, T.M.

Plasma potential enhancement by RF heating near the ion cyclotron frequency

2019-04-11T04:44:08Z

Plasma potential enhancement by RF heating near the ion cyclotron frequency Smith, D.K.; Brau, K.; Goodrich, P.; Irby, J.; Mauel, M.; Vey, B.D.; Post, R.; Sevillano, E.; Sullivan, J.

Finite temperature effects on the space-time evolution of two-stream instabilities

2019-04-12T20:42:34Z

Finite temperature effects on the space-time evolution of two-stream instabilities Francis, G.; Ram, A.K.; Bers, A.

Detection of alpha particles by CO-2 laser scattering

2019-04-12T20:42:34Z

Detection of alpha particles by CO-2 laser scattering Sigmar, D.; Vahala, L.; Vahala, G.

Line-tying of interchange modes in a hot electron plasma

2019-04-12T20:42:34Z

Line-tying of interchange modes in a hot electron plasma Gerver, M.J.; Lane, B.G.

Frequency scaling of the lower-hybrid current drive density limit in tokamak plasmas

2019-04-11T04:44:07Z

Frequency scaling of the lower-hybrid current drive density limit in tokamak plasmas Mayberry, M.J.; Porkolab, M.; Chen, K.I.; Fisher, A.S.; Griffin, D.; Kaplan, R.

Rippled-field magnetron (cross-field free electron laser)

2019-04-11T04:44:06Z

Rippled-field magnetron (cross-field free electron laser) Harteman, F.; Bekefi, G.; Shefer, R.E.

Progress in tokamak research at MIT

2019-04-11T04:44:06Z

Progress in tokamak research at MIT Parker, R.R.; Greenwald, M.; Luckhardt, S.C.; Marmar, E.S.; Porkolab, M.; Wolfe, S.M.

Self-consistent kinetic description of the free electron laser instability in a planar magnetic wiggler

2019-04-11T04:44:07Z

Self-consistent kinetic description of the free electron laser instability in a planar magnetic wiggler Davidson, R.C.; Wurtele, J.S.

Diagnosis of mildly relativistic electron distributions by cyclotron emission

2019-04-12T20:42:33Z

Diagnosis of mildly relativistic electron distributions by cyclotron emission Hutchinson, I.H.; Kato, K.

Low-frequency density fluctuations in the Alcator C tokamak

2019-04-10T18:25:46Z

Low-frequency density fluctuations in the Alcator C tokamak Watterson, R.L.

Whispering gallery mode gyrotron operation with a quasioptical antenna

2019-04-10T19:38:50Z

Whispering gallery mode gyrotron operation with a quasioptical antenna Danly, B.G.; Kreischer, K.E.; Mulligan, W.J.; Temkin, R.J.

High resolution X-ray spectroscopy diagnostics of high temperature plasmas

2019-04-11T04:44:04Z

High resolution X-ray spectroscopy diagnostics of high temperature plasmas Kallne, E.; Kallne, J.; Marmar, E.S.; Rice, J.E.

Optimization of gyroklystron efficiency

2019-04-12T20:42:32Z

Optimization of gyroklystron efficiency Tran, T.M.; Danly, B.G.; Kreischer, K.E.; Schutkeker, J.B.; Temkin, R.J.

Gyrotron with a high Q cavity for plasma scattering diagnostics

2019-04-12T20:42:32Z

Gyrotron with a high Q cavity for plasma scattering diagnostics Saito, H.; Danly, B.G.; Mulligan, W.J.; Temkin, R.J.; Woskoboinikow, P.

Analytic mirror equilibria with new long-thin terms

2019-04-12T20:42:33Z

Analytic mirror equilibria with new long-thin terms Goodman, D.L.; Freidberg, J.P.; Lane, B.

Free electron laser or cyclotron maser instability?

2019-04-10T18:26:16Z

Free electron laser or cyclotron maser instability? Bekefi, B.; Fajans, J.

Soft X-ray tomography on Alcator C

2019-04-10T16:47:42Z

Soft X-ray tomography on Alcator C Granetz, R.; Camacho, J.F.

Kinetic stability properties of an intense relativistic electron ring in a high-current betatron accelerator

2019-04-10T18:26:15Z

Kinetic stability properties of an intense relativistic electron ring in a high-current betatron accelerator Uhm, H.; Davidson, R.C.

Generalized nonlinear harmonic gyrotron theory

2019-04-12T20:42:32Z

Generalized nonlinear harmonic gyrotron theory Danly, B.G.; Temkin, R.J.

High brightness electrostatically focussed field emission electron gun for free electron laser applications

2019-04-10T18:26:14Z

High brightness electrostatically focussed field emission electron gun for free electron laser applications Kirkpatrick, D.A.; Shefer, R.E.; Bekefi, G.

Design of megewatt gyrotrons

2019-04-10T18:26:14Z

Design of megewatt gyrotrons Kreischer, K.; Danly, B.G.; Schutkeker, J.B.; Temkin, R.J.

Summary abstract:pellet fueling experiments in Alcator C

2019-04-10T18:26:15Z

Summary abstract:pellet fueling experiments in Alcator C Greenwald, M.; Parker, J.; Fiore, C.; Gandy, R.; Gomez, C.; Granetz, R.; Marmar, E.; Cool, S.; Milora, S.; Pappas, D.; Parker, R.; Pribyl, P.; Rice, J.; Terry, J.; Wolfe, S.

Long-time quasilinear evolution of the free electron laser instability for a relativistic electron beam propagating through a helical magnetic wiggler

2019-04-10T18:26:15Z

Long-time quasilinear evolution of the free electron laser instability for a relativistic electron beam propagating through a helical magnetic wiggler Davidson, R.C.; Yin, Y.Z.

Microwave studies of a tunable free electron laser in combined axial and wiggler magnetic fields

2019-04-12T20:42:31Z

Microwave studies of a tunable free electron laser in combined axial and wiggler magnetic fields Fajans, J.; Bekefi, G.; Yin, Y.Z.; Lax, B.

Particle confinement and the anomalous Doppler instability during combined inductive and lower-hybrid current drive

2019-04-12T20:42:31Z

Particle confinement and the anomalous Doppler instability during combined inductive and lower-hybrid current drive Luckhardt, S.C.; Chen, K.I.; Mayberry, M.J.; Porkolab, M.; Terumichi, Y.; Bekefi, G.; Dermott, F.S.; Rohatgi, R.

Kinetic equilibrium properties of relativistic nonneutral electron flow in a cylindrical diode with applied magnetic field

2019-04-10T18:26:12Z

Kinetic equilibrium properties of relativistic nonneutral electron flow in a cylindrical diode with applied magnetic field Davidson, R.C.; Uhm, H.S.

High power second harmonic emission and frequency locking in a 28 GHz gyrotron

2019-04-10T18:26:11Z

High power second harmonic emission and frequency locking in a 28 GHz gyrotron Danly, B.G.; Mulligan, W.J.; Temkin, R.J.; Sollner, T.C.

Influence of profile shape on the extraordinary-mode stability properties of relativistic nonneutral electron flow in a planar diode with applied magnetic field

2019-04-10T16:35:45Z

Influence of profile shape on the extraordinary-mode stability properties of relativistic nonneutral electron flow in a planar diode with applied magnetic field Davidson, R.C.; Tsang, K.T.

Collective instabilities driven by anode plasma ions and electrons in a nonrelativistic cylindrical diode with applied magnetic field

2019-04-12T20:42:30Z

Collective instabilities driven by anode plasma ions and electrons in a nonrelativistic cylindrical diode with applied magnetic field Davidson, R.C.; Tsang, K.T.; Uhm, H.S.

Quasilinear theory of diocotron instability for nonrelativistic nonneutral electron flow in a planar diode with applied magnetic field

2019-04-09T17:50:35Z

Quasilinear theory of diocotron instability for nonrelativistic nonneutral electron flow in a planar diode with applied magnetic field Davidson, R.C.

Kinetic stability properties of nonrelativistic nonneutral electron flow in a planar diode with applied magnetic field

2019-04-12T20:42:30Z

Kinetic stability properties of nonrelativistic nonneutral electron flow in a planar diode with applied magnetic field Davidson, R.C.

Observation and analysis of maser activity in a tokamak plasma

2019-04-10T18:26:10Z

Observation and analysis of maser activity in a tokamak plasma Gandy, R.F.; Hutchinson, I.H.; Yates, D.H.

Cavity mode analysis of plasma frequency waves in inhomogenous cylindrical plasmas

2019-04-12T20:42:24Z

Cavity mode analysis of plasma frequency waves in inhomogenous cylindrical plasmas Hutchinson, I.H.; Gandy, R.F.

Axisymmetric, wall-stabilized tandem mirrors

2019-04-12T20:42:25Z

Axisymmetric, wall-stabilized tandem mirrors Kesner, J.

High frequency gyrotron scattering diagnostic for instability studies on TARA

2019-04-12T20:42:28Z

High frequency gyrotron scattering diagnostic for instability studies on TARA Woskoboinikow, P.; Cohn, D.R.; Gerver, M.; Mulligan, W.J.; Post, R.S.; Temkin, R.J.; Trulsen, J.

Sawtooth oscillations in the visible continuum on Alcator C

2019-04-12T20:42:26Z

Sawtooth oscillations in the visible continuum on Alcator C Foord, M.E.; Marmar, E.S.

Generation of electromagnetic radiation from a rotating electron ring in a rippled magnetic field

2019-04-12T20:42:26Z

Generation of electromagnetic radiation from a rotating electron ring in a rippled magnetic field Yin, Y.Z.; Bekefi, G.

Observation of parametric instabilities in the lower hybrid range of frequencies in the Alcator C tokamak

2019-04-10T16:41:14Z

Observation of parametric instabilities in the lower hybrid range of frequencies in the Alcator C tokamak Takase, Y.; Porkolab, M.; Schuss, J.J.; Watterson, R.L.; Fiore, C.L.

Influence of finite radial geometry on coherent radiation by a relativistic electron beam in a longitudinal magnetic wiggler

2019-04-10T18:26:09Z

Influence of finite radial geometry on coherent radiation by a relativistic electron beam in a longitudinal magnetic wiggler Davidson, R.C.; Yin, Y.Z.

On the theory of pairwise coupling embedded in more local dispersion relations

2019-04-12T20:42:22Z

On the theory of pairwise coupling embedded in more local dispersion relations Fuchs, V.

Frequency pulling and band width measurements of a 140 GHz pulsed gyrotron

2019-04-11T03:55:27Z

Frequency pulling and band width measurements of a 140 GHz pulsed gyrotron Kreischer, K.E.; Danly, B.G.; Woskoboinikow, P.; Mulligan, W.J.; Temkin, R.J.

Low energy beam dumping in a TARA reactor design

2019-04-10T18:26:08Z

Low energy beam dumping in a TARA reactor design Li, X.Z.; Kesner, J.

Harmonic emission from high-power high-frequency gyrotrons

2019-04-09T16:05:40Z

Harmonic emission from high-power high-frequency gyrotrons Byerly, J.L.; Danly, B.G.; Kreischer, K.E.; Temkin, R.J.; Mulligan, W.J.; Woskoboinikow, P.

Lower hybrid wave propogation in toroidal plasmas

2019-04-10T18:26:08Z

Lower hybrid wave propogation in toroidal plasmas Schuss, J.J.

High efficiency operation of a 140 GHz pulsed gyrotron

2019-04-09T19:13:52Z

High efficiency operation of a 140 GHz pulsed gyrotron Kreischer, K.E.; Schutkeker, J.B.; Danly, B.G.; Mulligan, W.J.; Temkin, R.J.

Kinetic theory of the ponderomotive force near gyroresonance

2019-04-12T20:42:22Z

Kinetic theory of the ponderomotive force near gyroresonance Krapchev, V.B.

Quasilinear stabilization of the free electron laser instability for a relativistic electron beam propagating through a transverse helical wiggler magnetic field

2019-04-12T20:42:22Z

Quasilinear stabilization of the free electron laser instability for a relativistic electron beam propagating through a transverse helical wiggler magnetic field Dimos, A.; Davidson, R.C.

Steady state solution of the Fokker-Planck equation combined with unidirectional quasilinear diffusion under detailed balance conditions

2019-04-10T18:26:06Z

Steady state solution of the Fokker-Planck equation combined with unidirectional quasilinear diffusion under detailed balance conditions Hizanidis, K.

Transport theory; microscopic reversibility and symmetry

2019-04-10T18:26:07Z

Transport theory; microscopic reversibility and symmetry Molvig, K.; Hizanidis, K.

Impurity density calculations from spectroscopic measurements of visible and UV line emission on the Alcator C tokamak

2019-04-10T18:26:07Z

Impurity density calculations from spectroscopic measurements of visible and UV line emission on the Alcator C tokamak Moreno, J.C.; Marmar, E.S.

Constraints on very high beta tandem mirror reactor operation

2019-04-10T18:26:06Z

Constraints on very high beta tandem mirror reactor operation Potok, R.E.

Compton and Raman free electron laser stability properties for a cold electron beam propagating through a helical magnetic wiggler

2019-04-12T20:42:21Z

Compton and Raman free electron laser stability properties for a cold electron beam propagating through a helical magnetic wiggler Davies, J.A.; Davidson, R.C.; Johnston, G.L.

Observation of charge transfer population of n=2 excited states of Ar 16+ in tokamak plasmas

2019-04-12T20:42:21Z

Observation of charge transfer population of n=2 excited states of Ar 16+ in tokamak plasmas Kallne, E.; Kallne, J.; Dalgarno, A.; Marmar, E.S.; Rice, J.E.; Pradhan, A.K.

Enhancement of the reaction rate by ICRF heating

2019-04-10T18:26:05Z

Enhancement of the reaction rate by ICRF heating Krapchev, V.B.

Limiter hard x-ray emission studies during lower hybrid current drive experiments on the Alcator C tokamak

2019-04-10T18:26:05Z

Limiter hard x-ray emission studies during lower hybrid current drive experiments on the Alcator C tokamak Pappas, D.S.; Texter, S.C.; Gandy, R.F.; Lloyd, B.; Porkolab, M.

Simulation of phase space hole growth and the development of intermittent plasma turbulence

2019-04-12T20:42:19Z

Simulation of phase space hole growth and the development of intermittent plasma turbulence Berman, R.H.; Tetreault, D.J.; Dupree, T.H.

Spectrum and propagation of lower hybrid waves in the Alcator C tokamak

2019-04-12T20:42:20Z

Spectrum and propagation of lower hybrid waves in the Alcator C tokamak Watterson, R.L.; Takase, Y.; Bonoli, P.T.; Porkolab, M.

Observation of scattering of parametric using co2 laser scattering in Alcator C

2019-04-12T20:42:20Z

Observation of scattering of parametric using co2 laser scattering in Alcator C Takase, Y.; Watterson, R.L.; Porkolab, M.; Fiore, C.L.

Spectral measurements from a tunable, Raman, free electron maser

2019-04-12T20:42:21Z

Spectral measurements from a tunable, Raman, free electron maser Fajans, J.; Bekefi, G.; Yin, Y.Z.; Lax, B.

Energy confinement of high density pellet-fueled plasmas in Alcator C

2019-04-10T18:26:04Z

Energy confinement of high density pellet-fueled plasmas in Alcator C Greenwald, M.; Gwin, D.; Parker, J.; Wolfe, S.; Besen, M.; Camacho, F.; Fairfax, S.; Fiore, C.; Foord, M.; Gandy, R.; Gomez, C.; Granetz, R.; Bombard, B.; Lipschultz, B.; Lloyd, B.; Marmar, E.; Cool, S.; Pappas, D.; Petrasso, R.; Pribyl, P.; Rice, J.

Steady state RF current drive based upon the relativistic Fokker-Planck equation with quasilinear diffusion

2019-04-10T18:26:04Z

Steady state RF current drive based upon the relativistic Fokker-Planck equation with quasilinear diffusion Hizanidis, K.; Bers, A.

Tunable far infrared laser

2019-04-12T20:42:19Z

Tunable far infrared laser Danly, B.G.; Evangelides, S.G.; Temkin, R.J.; Lax, B.

Steady state solution for the runaway electron distribution function

2019-04-12T20:42:19Z

Steady state solution for the runaway electron distribution function Molvig, K.; Tekula, M.S.; Bers, A.

Millimeter wave emission from a rotating electron ring in a rippled magnetic field

2019-04-10T18:26:02Z

Millimeter wave emission from a rotating electron ring in a rippled magnetic field Bekefi, G.; Shefer, R.E.; Destler, W.W.

Transport of injected impurities in Heliotron E

2019-04-10T18:26:03Z

Transport of injected impurities in Heliotron E Rice, J.E.; Terry, J.L.; Marmar, E.S.; Motojima, O.; Kaneko, H.; Kondo, K.; Mizuuchi, T.; Basshou, S.; Mutoh, T.; Sano, F.; Sasaki, A.; Sato, M.; Sudo, S.; Zushi, H.; Iima, M.; Magome, K.; Ohbiki, T.; Iiyoshi, A.; Uo, K.

Precision measurements of the H-like x-ray spectrum of c1 and the 1s lamb-shift

2019-04-10T20:14:55Z

Precision measurements of the H-like x-ray spectrum of c1 and the 1s lamb-shift Kallne, E.; Kallne, J.

Coupling theory for ICRF heating of large tokamaks

2019-04-09T17:24:24Z

Coupling theory for ICRF heating of large tokamaks Ram, A.; Bers, A.

Detrapping stochastic particle instability for electron motion in combined longitudinal wiggler and radiation wave fields

2019-04-10T18:26:01Z

Detrapping stochastic particle instability for electron motion in combined longitudinal wiggler and radiation wave fields Davidson, R.C.; Mullin, W.A.

Impurity generation during intense lower hybrid heating experiments on the Alcator C tokamak

2019-04-10T18:26:01Z

Impurity generation during intense lower hybrid heating experiments on the Alcator C tokamak Marmar, E.S.; Foord, M.; Bombard, B.; Lipschultz, B.; Moreno, J.; Rice, J.; Terry, J.; Lloyd, B.; Porkolab, M.; Schuss, J.; Takase, Y.; Texter, S.; Fiore, C.; Gandy, R.; Granetz, R.; Greenwald, M.; Gwinn, D.; Cool, S.; Pappas, D.; Parker, R.R.; Pribyl, P.

MARFES: an edge plasma phenomenon

2019-04-12T20:42:17Z

MARFES: an edge plasma phenomenon Lipschultz, B.; Bombard, B.; Marmar, E.S.; Pickrell, M.M.; Terry, J.L.; Watterson, R.; Wolfe, S.M.

Influx and sources of medium and high Z intrinsic impurities in the Alcator C tokamak

2019-04-12T20:42:18Z

Influx and sources of medium and high Z intrinsic impurities in the Alcator C tokamak Rice, J.E.; Marmar, E.S.; Lipschultz, B.; Terry, J.L.

Alcator DCT: heat removal and impurity control in a proposed long pulsed tokamak

2019-04-12T20:42:17Z

Alcator DCT: heat removal and impurity control in a proposed long pulsed tokamak Lipschultz, B.; Montgomery, D.B.; Politzer, P.A.; Wolfe, S.M.

Macroscopic guiding-center stability theorem for nonrelativistic nonneutral electron flow in a cylindrical diode with applied magnetic field

2019-04-10T18:25:59Z

Macroscopic guiding-center stability theorem for nonrelativistic nonneutral electron flow in a cylindrical diode with applied magnetic field Davidson, R.C.

Steady state solution of a two-dimensional Fokker-Planck equation with strong RF diffusion

2019-04-10T18:25:59Z

Steady state solution of a two-dimensional Fokker-Planck equation with strong RF diffusion Krapchev, V.B.; Hewett, D.W.; Bers, A.

Macroscopic electrostatic stability properties of nonrelativistic nonneutral electron flow in a cylindrical diode with applied magnetic field

2019-04-12T20:42:16Z

Macroscopic electrostatic stability properties of nonrelativistic nonneutral electron flow in a cylindrical diode with applied magnetic field Davidson, R.D.; Tsang, K.

Radially confined relativistic electron beam equilibria for longitudinal wiggler free electron laser applications

2019-04-12T20:42:16Z

Radially confined relativistic electron beam equilibria for longitudinal wiggler free electron laser applications Davidson, R.C.

Observation of Thomson scattering from ion thermal fluctuations in a tokamak plasma with a 385 micrometer laser

2019-04-10T18:25:58Z

Observation of Thomson scattering from ion thermal fluctuations in a tokamak plasma with a 385 micrometer laser Woskoboinikow, P.; Mulligan, W.J.; Machuzak, J.; Cohn, D.R.; Temkin, R.J.; Sollner, T.C.; Lax, B.

Engineering aspects of lower hybrid microwave injection into the Alcator C tokamak

2019-04-10T18:25:58Z

Engineering aspects of lower hybrid microwave injection into the Alcator C tokamak Schuss, J.J.; Porkolab, M.; Griffin, D.; Barilovits, S.; Besen, M.; Bredin, C.; Chihoski, G.; Israel, H.; Pierce, N.; Reiser, D.; Rice, K.

Diffusion of electrons by coherent wavepackets

2019-04-12T20:42:15Z

Diffusion of electrons by coherent wavepackets Fuchs, V.; Krapchev, V.; Ram, A.; Bers, A.

Plasma-vacuum interface problems in magnetohydrodynamics

2019-04-12T20:42:15Z

Plasma-vacuum interface problems in magnetohydrodynamics Goedbloed, J.P.

Collisional effects on trapped particle modes in tandem mirrors

2019-04-10T18:25:57Z

Collisional effects on trapped particle modes in tandem mirrors Lane, B.

Studies of neutron emission during the start-up phase of the Alcator C tokamak

2019-04-12T20:41:49Z

Studies of neutron emission during the start-up phase of the Alcator C tokamak Pappas, D.S.; Furnstahl, R.J.; Kochanski, G.P.; Wysocki, F.J.

End effects of a bifilar magnetic wiggler

2019-04-12T20:41:49Z

End effects of a bifilar magnetic wiggler Fajans, J.

Effect of equilibrium radial electric field on trapped particle stability in tandem mirrors

2019-04-12T20:41:49Z

Effect of equilibrium radial electric field on trapped particle stability in tandem mirrors Kesner, J.; Lane, B.

Stellarator equilibria and the problem of position control

2019-04-12T20:41:50Z

Stellarator equilibria and the problem of position control Friedberg, J.P.; Politzer, P.A.; Rosenau, P.

Velocity diagnostics of mildly relativistic, high current electron beams

2019-04-10T18:25:56Z

Velocity diagnostics of mildly relativistic, high current electron beams Shefer, R.E.; Yin, Y.Z.; Bekefi, G.

Effects of plasma elongation on magnetics of continuous-coil tokamak reactors

2019-04-11T08:39:50Z

Effects of plasma elongation on magnetics of continuous-coil tokamak reactors Bobrov, E.; Bromberg, L.

Resonant helically distorted relativistic electron beam equilibria for free electron laser applications

2019-04-10T18:25:56Z

Resonant helically distorted relativistic electron beam equilibria for free electron laser applications Johnston, G.L.; Davidson, R.C.

Measurement of the D-D fusion neutron energy spectrum and variation of the peak width with plasma ion temperature

2019-04-12T20:41:48Z

Measurement of the D-D fusion neutron energy spectrum and variation of the peak width with plasma ion temperature Fisher, W.A.; Chen, S.H.; Gwinn, D.; Parker, R.R.

Dispersion characteristics of a free electron laser with a linearly polarized wiggler and axial guide field

2019-04-12T20:41:48Z

Dispersion characteristics of a free electron laser with a linearly polarized wiggler and axial guide field Yin, Y.Z.; Bekefi, G.

Parametric phenomena in electron cyclotron resonance heating of tokamak plasmas

2019-04-09T16:07:25Z

Parametric phenomena in electron cyclotron resonance heating of tokamak plasmas Stefan, V.; Bers, A.

Submillimeter-wave dumps for fusion plasma diagnostics

2019-04-10T18:25:55Z

Submillimeter-wave dumps for fusion plasma diagnostics Woskoboinikow, P.; Erickson, R.; Mulligan, W.J.

X-ray line intensities for ions of the helium isoelectronic sequence in high temperature plasmas

2019-04-12T20:41:47Z

X-ray line intensities for ions of the helium isoelectronic sequence in high temperature plasmas Kallne, E.; Kallne, J.; Pradhan, A.

Electron cyclotron heating in the Constance 2

2019-04-12T20:41:45Z

Electron cyclotron heating in the Constance 2 Mauel, M.

Parametric excitation of ion-sound quasi-modes during lower hybrid heating experiments in tokamaks

2019-04-12T20:41:45Z

Parametric excitation of ion-sound quasi-modes during lower hybrid heating experiments in tokamaks Takase, Y.; Porkolab, M.

Stimulated emission from a relativistic electron beam in a variable parameter longitudinal magnetic wiggler

2019-04-12T20:41:46Z

Stimulated emission from a relativistic electron beam in a variable parameter longitudinal magnetic wiggler Mullin, W.A.; Davidson, R.C.; Johnston, G.

Radiation measurements from a rippled-field magnetron (crossed-field FEL)

2019-04-11T08:39:50Z

Radiation measurements from a rippled-field magnetron (crossed-field FEL) Bekefi, G.; Shefer, R.E.; Nevins, B.D.

Nonlinear travelling-wave equilibria for free electron laser applications

2019-04-10T18:25:53Z

Nonlinear travelling-wave equilibria for free electron laser applications Lane, B.; Davidson, R.C.

Radiation measurements from an inverted relativistic magnetron

2019-04-10T18:25:55Z

Radiation measurements from an inverted relativistic magnetron Close, R.A.; Palevsky, A.; Bekefi, G.

Fast neutron spectrometer for D-D fusion neutron measurements at the Alcator C tokamak

2019-04-12T20:41:44Z

Fast neutron spectrometer for D-D fusion neutron measurements at the Alcator C tokamak Fisher, W.A.; Chen, S.H.; Gwinn, D.; Parker, R.R.

On tearing modes in a resistive medium

2019-04-12T20:41:44Z

On tearing modes in a resistive medium Rosenau, P.

Optimization and Monte Carlo modeling of bundle divertors

2019-04-09T18:39:40Z

Optimization and Monte Carlo modeling of bundle divertors Yang, T.F.; Wan, A.; Potok, R.; Blackfield, D.T.

Growth of phase space density holes

2019-04-09T16:04:58Z

Growth of phase space density holes Dupree, T.H.

Multimode oscillation and mode competition in high frequency gyrotrons

2019-04-11T08:39:47Z

Multimode oscillation and mode competition in high frequency gyrotrons Kreischer, K.E.; Temkin, R.J.; Fetterman, H.R.; Mulligan, W.J.

High resolution x-ray spectra from molybdenum ions in the Alcator C tokamak

2019-04-11T08:39:49Z

High resolution x-ray spectra from molybdenum ions in the Alcator C tokamak Kallne, E.; Kallne, J.; Cowan, R.D.

Cross-field free electron laser instability for a tenuous electron beam

2019-04-12T20:41:43Z

Cross-field free electron laser instability for a tenuous electron beam Davidson, R.C.; Mullin, W.A.

Modular commercial tokamak reactor with day long pulses

2019-04-11T08:39:45Z

Modular commercial tokamak reactor with day long pulses Bromberg, L.; Cohn, D.R.; Williams, J.E.

Observation of self-binding turbulent fluctuations in simulation plasma and their relevance to plasma kinetic theories

2019-04-11T08:39:46Z

Observation of self-binding turbulent fluctuations in simulation plasma and their relevance to plasma kinetic theories Berman, R.H.; Tetreault, D.J.; Dupree, T.H.

Lagrangian formulation of transport theory; like-particle collisional transport and variational principle

2019-04-11T08:39:46Z

Lagrangian formulation of transport theory; like-particle collisional transport and variational principle Hizanidis, K.; Molvig, K.; Bernstein, I.B.

Stabilization of the tearing mode in low density tokamak plasmas by turbulent electron diffusion

2019-04-09T16:24:55Z

Stabilization of the tearing mode in low density tokamak plasmas by turbulent electron diffusion Esarey, E.; Friedberg, J.P.; Molvig, K.; Rij, W.I.; Beasley, C.O.

Breakdown of Onsager symmetry in neoclassical transport theory

2019-04-12T20:41:43Z

Breakdown of Onsager symmetry in neoclassical transport theory Molvig, K.; Lidsky, L.M.; Hizanidis, K.; Bernstein, L.B.

Three-dimensional theory of waveguide-plasma coupling

2019-04-09T17:18:00Z

Three-dimensional theory of waveguide-plasma coupling Bers, A.; Theilhaber, K.S.

On impurity transport in tokamaks

2019-04-11T08:39:45Z

On impurity transport in tokamaks Seguin, F.; Petrasso, R.; Marmar, E.S.

Growth rate of the clump instability

2019-04-12T20:41:42Z

Growth rate of the clump instability Tetreault, D.J.

Multi-wire proportional counter for soft x-ray detection

2019-04-12T20:41:39Z

Multi-wire proportional counter for soft x-ray detection Kallne, J.; Kallne, E.; Atencio, L.G.; Morris, C.L.; Thompson, A.C.

Bifilar wiggler inductance

2019-04-12T20:41:40Z

Bifilar wiggler inductance Fajans, J.

Fully-ionized and total silicon abundances in the Alcator C tokamak

2019-04-12T20:41:40Z

Fully-ionized and total silicon abundances in the Alcator C tokamak Petrasso, R.; Seguin, F.H.; Loter, N.G.; Marmar, E.S.; Rice, J.

Ion cyclotron resonance heating studies in the central cell of the Phaedrus tandem mirror

2019-04-11T08:39:38Z

Ion cyclotron resonance heating studies in the central cell of the Phaedrus tandem mirror Vey, B.D.; Breun, R.A.; Golovato, S.N.; Molvik, A.V.; Smatlak, D.K.; Smith, D.K.; Yujiri, L.

High resolution x-ray spectroscopy for diagnostics of single tokamak discharges

2019-04-11T08:39:38Z

High resolution x-ray spectroscopy for diagnostics of single tokamak discharges Kallne, E.; Kallne, J.

X-ray diagnostics of tokamak plasmas

2019-04-12T20:41:37Z

X-ray diagnostics of tokamak plasmas Kallne, E.; Kallne, J.

385 micrometer D-two O laser linewidth measurements to -60 dB

2019-04-12T20:41:37Z

385 micrometer D-two O laser linewidth measurements to -60 dB Woskoboinikow, P.; Mulligan, W.J.; Erickson, R.

Observation of H- and He- like x-ray line emission in high density tokamak plasmas

2019-04-09T17:59:36Z

Observation of H- and He- like x-ray line emission in high density tokamak plasmas Kallne, E.; Rice, J.E.; Kallne, J.

Low beta pulsed tokamak as a modular commercial reactor with very long pulses

2019-04-11T08:39:37Z

Low beta pulsed tokamak as a modular commercial reactor with very long pulses Cohn, D.R.; Williams, J.E.; Bromberg, L.

100kW, 140 GHz pulsed gyrotron

2019-04-11T07:34:23Z

100kW, 140 GHz pulsed gyrotron Temkin, R.J.; Kreischer, K.E.; Mulligan, W.J.; Cabe, A.; Fetterman, H.R.

Impurity injection experiments on the Alcator C

2019-04-12T20:41:34Z

Impurity injection experiments on the Alcator C Marmar, E.S.; Rice, J.E.; Terry, J.L.

Quasilinear theory calculation of ion tails and neutron rates during lower hybrid heating in Alcator A

2019-04-12T20:41:34Z

Quasilinear theory calculation of ion tails and neutron rates during lower hybrid heating in Alcator A Schuss, J.J.; Antonsen, T.M.; Porkolab, M.

Application of advanced millimeter/far-infrared sources to collective Thomson scattering plasma diagnostics

2019-04-12T20:41:34Z

Application of advanced millimeter/far-infrared sources to collective Thomson scattering plasma diagnostics Woskoboinikow, P.; Cohn, D.R.; Temkin, R.J.

Analysis of toroidal magnet systems on the basis of the Reissner shell theory

2019-04-12T20:41:36Z

Analysis of toroidal magnet systems on the basis of the Reissner shell theory Bobrov, E.S.; Schultz, J.H.

Quasilinear calculation of ion tails and neutron rates in a D-T plasma due to lower hybrid waves

2019-04-11T07:34:22Z

Quasilinear calculation of ion tails and neutron rates in a D-T plasma due to lower hybrid waves Schuss, J.J.

The far UV emission spectrum of hydrogen

2019-04-11T07:34:23Z

The far UV emission spectrum of hydrogen Terry, J.L.

Higher harmonic emission by a relativistic electron beam in a longitudinal magnetic wiggler

2019-04-12T20:41:31Z

Higher harmonic emission by a relativistic electron beam in a longitudinal magnetic wiggler Davidson, R.C.; Mullin, W.

Kinetic wave expansion for the plasma fields generated by an external coil in a slab geometry

2019-04-12T20:41:33Z

Kinetic wave expansion for the plasma fields generated by an external coil in a slab geometry Vey, B.D.

Langer's method for weakly bound states of the helmholtz equation with symmetric profiles

2019-04-12T20:41:32Z

Langer's method for weakly bound states of the helmholtz equation with symmetric profiles Johnston, G.L.

MHD equilibrium and stability properties of a bipolar current loop

2019-04-12T20:41:33Z

MHD equilibrium and stability properties of a bipolar current loop Xue, M.L.; Chen, J.

Stochastic particle instability for electron motion in combined helical wiggler, radiation and longitudinal wave fields

2019-04-12T20:41:31Z

Stochastic particle instability for electron motion in combined helical wiggler, radiation and longitudinal wave fields Davidson, R.C.; Mullin, W.A.

Ideal magnetohydrodynamics stability of a high beta tokamak with superimposed helical fields

2019-04-11T07:34:21Z

Ideal magnetohydrodynamics stability of a high beta tokamak with superimposed helical fields Sherwell, D.; Freidberg, J.P.; Berge, J.

Computer simulation of nonlinear ion-electron instability

2019-04-09T18:08:44Z

Computer simulation of nonlinear ion-electron instability Berman, R.H.; Tetreault, D.J.; Dupree, T.H.; Ghali, T.

Rippled-Field Magnetron

2019-04-12T20:41:31Z

Rippled-Field Magnetron Bekefi, G.

Density threshold for MHD activity in Alcator C

2019-04-09T16:44:24Z

Density threshold for MHD activity in Alcator C Granetz, R.S.

Ion resonance instability in a modified betatron accelerator

2019-04-10T20:07:14Z

Ion resonance instability in a modified betatron accelerator Uhm, H.S.; Davidson, R.C.

Multichannel light detector system for visible continuum measurements on Alcator C

2019-04-11T07:34:17Z

Multichannel light detector system for visible continuum measurements on Alcator C Foord, M.E.; Marmar, E.S.; Terry, J.L.

Intense free electron laser harmonic wiggler in a longitudinal magnetic wiggler

2019-04-09T16:15:24Z

Intense free electron laser harmonic wiggler in a longitudinal magnetic wiggler Davidson, R.C.; Mullin, W.A.

Linear theory of coupling EM power from waveguide arrays to a plasma in a magnetic field

2019-04-12T20:41:26Z

Linear theory of coupling EM power from waveguide arrays to a plasma in a magnetic field Bers, A.; Theilhaber, K.S.

Lagrangian formulation of neoclassical transport theory

2019-04-12T20:41:27Z

Lagrangian formulation of neoclassical transport theory Bernstein, I.B.; Molvig, K.

Retarded time superposition principle and the relativistic collision operator

2019-04-10T20:22:47Z

Retarded time superposition principle and the relativistic collision operator Hizanidis, K.; Molvig, K.; Swartz, K.

Stimulated emission from relativistic electrons passing through a spatially periodic longitudinal magnetic field

2019-04-12T20:41:26Z

Stimulated emission from relativistic electrons passing through a spatially periodic longitudinal magnetic field Mullin, W.A.; Bekefi, G.

Phase space dynamics

2019-04-12T20:41:26Z

Phase space dynamics Tetreault, D.J.

Stability properties of an intense relativistic nonneutral electron ring in a modified betatron accelerator

2019-04-11T07:34:11Z

Stability properties of an intense relativistic nonneutral electron ring in a modified betatron accelerator Davidson, R.C.; Uhm, H.S.

Nonlinear coupling to lower hybrid waves in a tokamak plasma

2019-04-11T07:34:13Z

Nonlinear coupling to lower hybrid waves in a tokamak plasma Theilhaber, K.

Low gain free electron laser near cyclotron resonance

2019-04-11T07:34:12Z

Low gain free electron laser near cyclotron resonance Mullin, W.; Davidson, R.C.

Tandem mirror hot electron anchor

2019-04-11T07:34:12Z

Tandem mirror hot electron anchor Kesner, J.; Post, R.S.; Smith, D.K.; Baldwin, D.E.; Lee, Y.C.

Two-stream, free electron lasers

2019-04-11T07:34:14Z

Two-stream, free electron lasers Bekefi, G.; Jacobs, K.D.

Generation of RF currents by lower-hybrid wave injection in the Versator II tokamak

2019-04-11T07:34:11Z

Generation of RF currents by lower-hybrid wave injection in the Versator II tokamak Luckhardt, S.C.; Porkolab, M.; Knowlton, S.F.; Chen, K; Fisher, A.S.; Dermott, F.S.; Mayberry, M.

Probe measurements of the boundary plasma in Alcator C

2019-04-11T07:34:08Z

Probe measurements of the boundary plasma in Alcator C Hayzen, A.J.; Overskei, D.O.; Moreno, J.

Lowbitron- a source of coherent electromagnetic radiation

2019-04-11T07:34:09Z

Lowbitron- a source of coherent electromagnetic radiation Mullin, W.A.; Bekefi, G.

Tandem mirror with axisymmetric central cell ion

2019-04-12T20:41:23Z

Tandem mirror with axisymmetric central cell ion Kesner, J.; Vey, B.D.; Post, R.S.; Smith, D.K.

Free electron laser instability for a relativistic solid electron beam in a helical wiggler field

2019-04-12T20:41:21Z

Free electron laser instability for a relativistic solid electron beam in a helical wiggler field Uhm, H.S.; Davidson, R.C.

Breakdown of Onsager symmetry in neoclassical transport theory

2019-04-12T20:41:21Z

Breakdown of Onsager symmetry in neoclassical transport theory Molvig, K.; Lidsky, L.M.; Hizanidis, K.; Bernstein, I.B.

Cyclotron emission from intense relativistic electron beams in uniform and rippled magnetic fields

2019-04-12T20:41:24Z

Cyclotron emission from intense relativistic electron beams in uniform and rippled magnetic fields Shefer, R.E.; Bekefi, G.

Analytic theory of a tapered gyrotron resonator

2019-04-11T07:34:06Z

Analytic theory of a tapered gyrotron resonator Temkin, R.

Search of optimized bundle divertors

2019-04-11T07:34:06Z

Search of optimized bundle divertors Yang, T.F.; Potok, R.; Wan, A.; Blackfield, D.; Fisher, J.

Continuum x-ray emission from the Alcator A tokamak

2019-04-11T07:34:07Z

Continuum x-ray emission from the Alcator A tokamak Rice, J.E.; Molvig, K.; Helava, H.T.

Natural circulation of electrically conducting liquids in fusion reactor blankets

2019-04-11T07:34:08Z

Natural circulation of electrically conducting liquids in fusion reactor blankets Gierszewski, P.J.; Mikic, B.; Todreas, N.E.

Diffusive wiggler-a spatially periodic magnetic pump for free-electron lasers

2019-04-12T20:41:18Z

Diffusive wiggler-a spatially periodic magnetic pump for free-electron lasers Jacobs, K.D.; Bekefi, G.; Freeman, J.R.

Theory of nonlinear ion-electron instability

2019-04-10T07:27:25Z

Theory of nonlinear ion-electron instability Ghali, T.; Dupree, T.H.

Conceptual design of bundle divertors

2019-04-11T07:33:53Z

Conceptual design of bundle divertors Yang, T.F.; Rapperport, E.J.; Tracey, J.E.; Langton, W.; Blackfield, D.; Wan, A.; Montgomery, D.B.; Fisher, J.; Cheng, E.T.

MHD equilibrium and stability properties of solar magnetic loops

2019-04-11T07:33:49Z

MHD equilibrium and stability properties of solar magnetic loops Xue, M.L.

Ash exhaust causes limitation in steady state tokamak fusion reactors

2019-04-11T07:33:50Z

Ash exhaust causes limitation in steady state tokamak fusion reactors Xue, M.L.

Direct energy convertor for UW tandem mirror reactor

2019-04-12T20:41:14Z

Direct energy convertor for UW tandem mirror reactor Yang, T.F.; Maurev, W.

Oscillating limiter concepts

2019-04-12T20:41:13Z

Oscillating limiter concepts Xue, M.L.; Yang, T.F.

Mode coupling and anomalous dissipation in MHD turbulence

2019-04-12T20:41:14Z

Mode coupling and anomalous dissipation in MHD turbulence Tetreault, D.J.

Influence of wall impedance of the elctron cyclotron maser instability

2019-04-11T07:33:47Z

Influence of wall impedance of the elctron cyclotron maser instability Uhm, H.S.; Davidson, R.C.

Numerical simulation of oscillating magnetrons

2019-04-09T15:25:07Z

Numerical simulation of oscillating magnetrons Palevsky, A.; Bekefi, G.; Drobot, A.T.

Free electron laser instability for a relativistic annular electron beam in a helical wiggler field

2019-04-11T07:33:47Z

Free electron laser instability for a relativistic annular electron beam in a helical wiggler field Uhm, H.S.; Davidson, R.C.

Theory of two point correlation function in Vlasov plasma

2019-04-11T07:33:48Z

Theory of two point correlation function in Vlasov plasma Ghali, T.; Dupree, T.H.

Tearing-mode stability properties of a diffuse anisotropic field-reversed ion layer at marginal stability

2019-04-12T20:41:13Z

Tearing-mode stability properties of a diffuse anisotropic field-reversed ion layer at marginal stability Chen, J.; Davidson, R.C.

Energy release mechanism of current loops in the solar atmosphere: solar flares and corona heating

2019-04-12T20:41:13Z

Energy release mechanism of current loops in the solar atmosphere: solar flares and corona heating Xue, M.L.; Chen, J.

On the electron-cyclotron resonance heating in plasmas with arbitrary stratification of the magnetic field

2019-04-11T07:33:46Z

On the electron-cyclotron resonance heating in plasmas with arbitrary stratification of the magnetic field Friedland, L.; Porkolab, M.

Mode excitation in a gyrotron operating at the fundamental

2019-04-12T20:41:12Z

Mode excitation in a gyrotron operating at the fundamental Kreischer, K.E.; Temkin, R.J.

Theory of free electron laser instability in a relativistic annual electron beam

2019-04-11T07:33:45Z

Theory of free electron laser instability in a relativistic annual electron beam Davidson, R.C.; Uhm, H.S.

Theory of mode-conversion in weakly inhomogeneous plasma

2019-04-11T07:33:45Z

Theory of mode-conversion in weakly inhomogeneous plasma Fuchs, V.; Ko, K.; Bers, A.

Excitation of ion-cyclotron harmonic waves in lower-hybrid heating

2019-04-12T20:41:11Z

Excitation of ion-cyclotron harmonic waves in lower-hybrid heating Villalon, E.

Helically distorted relativistic electron beam equilibria for free electron laser applications

2019-04-12T20:41:10Z

Helically distorted relativistic electron beam equilibria for free electron laser applications Davidson, R.C.; Uhm, H.S.

Nonlinear coupling of lower hybrid waves at the edge of tokamak plasmas

2019-04-12T20:41:11Z

Nonlinear coupling of lower hybrid waves at the edge of tokamak plasmas Krapchev, V.B.; Theilhaber, K.S.; Ko, K.; Bers, A.

Relativistic field emission diodes in free electron Raman lasers

2019-04-09T18:28:09Z

Relativistic field emission diodes in free electron Raman lasers Shefer, R.E.; Bekefi, G.

Calculation of turbulent diffusion for the Chirikov-Taylor model

2019-04-10T21:09:05Z

Calculation of turbulent diffusion for the Chirikov-Taylor model Rechester, A.B.; White, R.B.

Lower hybrid heating in the Alcator A tokamak

2019-04-12T20:41:09Z

Lower hybrid heating in the Alcator A tokamak Schuss, J.J.; Porkolab, M.; Takase, Y.; Cope, D.; Fairfax, S.; Greenwald, M.; Gwinn, D.; Hutchinson, I.H.; Kusse, B.; Marmar, E.; Overskei, D.; Pappas, D.; Parker, R.R.; Scaturro, L.; West, J.; Wolfe, S.

Efficacy of passive limiters pumping of neutral particles

2019-04-12T20:41:10Z

Efficacy of passive limiters pumping of neutral particles Overskei, D.O.

Free electron laser pump produced by magnetic diffusion

2019-04-12T20:41:10Z

Free electron laser pump produced by magnetic diffusion Jacobs, K.D.; Shefer, R.E.; Bekefi, G.

Confinement of injected silicon in the Alcator A tokamak

2019-04-09T18:02:24Z

Confinement of injected silicon in the Alcator A tokamak Marmar, E.S.; Rice, J.E.; Allen, S.A.

Tearing-mode stability properties of a field-reversed ion layer at marginal stability

2019-04-11T04:22:19Z

Tearing-mode stability properties of a field-reversed ion layer at marginal stability Chen, J.; Davidson, R.C.

Linear theory of an electron cyclotron maser operating at the fundamental

2019-04-10T07:30:47Z

Linear theory of an electron cyclotron maser operating at the fundamental Kreischer, K.E.; Temkin, R.J.

Fast compressional alfven waves in a tokamak

2019-04-12T20:41:08Z

Fast compressional alfven waves in a tokamak Takahashi, H.

Ion thermal conductivity in torsatrons

2019-04-12T20:41:09Z

Ion thermal conductivity in torsatrons Potok, R.; Politzer, P.A.; Lidsky, L.

Adiabatic theory of current generation by nonlinear waves in a Vlasov plasma

2019-04-11T04:22:19Z

Adiabatic theory of current generation by nonlinear waves in a Vlasov plasma Krapchev, V.B.; Ram, A.K.

Resonant parametric excitation in lower-hybrid heating of tokamak plasma

2019-04-12T20:41:07Z

Resonant parametric excitation in lower-hybrid heating of tokamak plasma Villalon, E.

Creating stable tokamak reactor equilibria by supplemental heating

2019-04-12T20:41:07Z

Creating stable tokamak reactor equilibria by supplemental heating Harten, L.; Fuchs, V.; Bers, A.

Self-consistent Vlasov description of the free electron laser instability in a relativistic electron beam with uniform density

2019-04-12T20:41:08Z

Self-consistent Vlasov description of the free electron laser instability in a relativistic electron beam with uniform density Davidson, R.C.; Uhm, H.S.

Molybdenum and chlorine x-ray emission from Alcator A

2019-04-09T16:02:40Z

Molybdenum and chlorine x-ray emission from Alcator A Rice, J.E.; Marmar, E.S.; Coan, T.; Allen, S.L.; Cowan, R.D.

Low-frequency flute instabilities in intense nonneutral electron and ion beams

2019-04-12T21:53:58Z

Low-frequency flute instabilities in intense nonneutral electron and ion beams Uhm, H.S.; Davidson, R.C.

Depletion of ripple trapped particles in the Alcator tokamaks

2019-04-12T21:53:58Z

Depletion of ripple trapped particles in the Alcator tokamaks Greenwald, M.; Schuss, J.J.; Cope, D.

Effect of magnetic field ripple on energetic ions in Alcator A

2019-04-09T16:01:22Z

Effect of magnetic field ripple on energetic ions in Alcator A Schuss, J.J.

Coupling to the fast wave at lower hybrid frequencies

2019-04-12T21:53:57Z

Coupling to the fast wave at lower hybrid frequencies Theilhaber, K.; Bers, A.

Observations of fluctuating electromagnetic emission at the plasma frequency in Alcator tokamaks

2019-04-12T21:53:58Z

Observations of fluctuating electromagnetic emission at the plasma frequency in Alcator tokamaks Hutchinson, I.H.; Kissel, S.E.

Effect of waveguide boundary conditions on the backscatter of lower hybrid waves

2019-04-10T19:42:06Z

Effect of waveguide boundary conditions on the backscatter of lower hybrid waves Schuss, J.J.

Note on tokamak ignition equilibria and thermal stability

2019-04-12T21:53:57Z

Note on tokamak ignition equilibria and thermal stability Fuchs, V.; Harten, L.; Bers, A.

Electrically pumped, relativistic, free electron wave generators

2019-04-12T21:53:56Z

Electrically pumped, relativistic, free electron wave generators Bekefi, G.

Plasma frequency radiation in tokamaks

2019-04-12T21:54:55Z

Plasma frequency radiation in tokamaks Swartz, K.; Hutchinson, I.H.; Molvig, K.

Transient amplification of shear alfven waves concommitant development of the ballooning instability

2019-04-12T21:53:56Z

Transient amplification of shear alfven waves concommitant development of the ballooning instability Lau, Y.Y.; Davidson, R.C.; Hui, B.

Thermal equilibrium properties of an intense ion beam with rotational and axial motion

2019-04-12T21:54:54Z

Thermal equilibrium properties of an intense ion beam with rotational and axial motion Chen, J.; Davidson, R.C.

Kinetic description of coupled transverse oscillations in an intense relativistic electron beam-plasma system

2019-04-12T21:54:54Z

Kinetic description of coupled transverse oscillations in an intense relativistic electron beam-plasma system Uhm, H.S.; Davidson, R.C.

Effect of wall corrugations on the lower hybrid wave spectrum of a waveguide array

2019-04-10T09:18:59Z

Effect of wall corrugations on the lower hybrid wave spectrum of a waveguide array Scherbinin, O.N.; Schuss, J.J.

Coupled dipole oscillations in an intense relativistic electron beam

2019-04-10T09:19:00Z

Coupled dipole oscillations in an intense relativistic electron beam Davidson, R.C.; Uhm, H.S.

Wave coupling effects in the nonlinear evolution of the beam-plasma instability

2019-04-10T09:19:00Z

Wave coupling effects in the nonlinear evolution of the beam-plasma instability Throop, A.L.; Parker, R.R.

Tearing mode instability in a field-reversed ion layer

2019-04-10T09:18:55Z

Tearing mode instability in a field-reversed ion layer Uhm, H.S.; Davidson, R.C.

Stimulated raman scattering by an intense relativistic electron beam subjected to a rippled electric field

2019-04-09T19:09:15Z

Stimulated raman scattering by an intense relativistic electron beam subjected to a rippled electric field Bekefi, G.; Shefer, R.E.

Lower hybrid wave heating in the Alcator A tokamak

2019-04-10T09:18:59Z

Lower hybrid wave heating in the Alcator A tokamak Schuss, J.J.; Fairfax, S.; Kusse, B.; Parker, R.R.; Porkolab, M.; Gwinn, D.; Hutchinson, I.H.; Marmar, E.S.; Overski, D.; Pappas, D.; Scaturro, L.S.; Wolfe, S.

Nonlocal hybrid-kinetic stability analysis of the drift-cone instability

2019-04-12T21:54:54Z

Nonlocal hybrid-kinetic stability analysis of the drift-cone instability Davidson, R.C.; Uhm, H.S.; Aamodt, R.E.

Stark broadening induced by the intense electric field of a pulsed relativistic magnetron

2019-04-10T23:59:52Z

Stark broadening induced by the intense electric field of a pulsed relativistic magnetron Shefer, R.E.; Bekefi, G.

Review of RF heating

2019-04-10T09:18:58Z

Review of RF heating Porkolab, M.

Stability properties of a field-reversed ion layer in a background plasma

2019-04-10T19:30:14Z

Stability properties of a field-reversed ion layer in a background plasma Uhm, H.S.; Davidson, R.C.

Microwave emission from pulsed, relativistic e-beam diodes. I: The smooth-bore magnetron

2019-04-12T21:54:53Z

Microwave emission from pulsed, relativistic e-beam diodes. I: The smooth-bore magnetron Orzechowski, T.J.; Bekefi, G.

Microwave emission from pulsed, relativistic e-beam diodes. II: The multiresonator magnetron

2019-04-12T21:54:53Z

Microwave emission from pulsed, relativistic e-beam diodes. II: The multiresonator magnetron Palevsky, A.; Bekefi, G.

Test of a conduction-cooled, prototype, superconducting magnet for a compact cyclotron

2019-04-10T09:18:57Z

Test of a conduction-cooled, prototype, superconducting magnet for a compact cyclotron Michael, P.C.

Suppression of W (sub ci) instability

2019-04-10T09:18:58Z

Suppression of W (sub ci) instability Klinkowstein, R.E.; Smullin, L.D.

Stimulated raman scattering by an intense relativistic electron beam subjected to a rippled electric field

2019-04-12T21:54:52Z

Stimulated raman scattering by an intense relativistic electron beam subjected to a rippled electric field Bekefi, G.; Shefer, R.E.

A new model to account for track overlap in CR-39 data.

2019-04-10T09:18:57Z

A new model to account for track overlap in CR-39 data. Zylstra, A.B.; Frenje, J.A.; Seguin, F.H.; Johsnon, M.; Casey, D.T.; Rosenberg, M.J.; Waugh, C.; Sinenian, N.; Manuel, M.J.; Li, C.K.; Petrasso, R.D.; Kim, Y.; Herrmann, H.W.

Upgrade of the MIT Linear Electrostatic Ion Accelerator (LEIA) for nuclear diagnostics development for Omega, Z and the NIF

2019-04-12T21:54:51Z

Upgrade of the MIT Linear Electrostatic Ion Accelerator (LEIA) for nuclear diagnostics development for Omega, Z and the NIF Sinenian, N.; Manuel, M.J.; Zylstra, A.B.; Rosenberg, M.; Waugh, C.J.; Rinderknecht, H.G.; Casey, D.T.; Sio, H.; Ruszczynski, J.K.; Zhou, L.; Johnson, M.; Frenje, J.A.; Seguin, F.H.; Li, C.K.; Petrasso, R.D.; Ruiz, C.L.; Leeper, R.J.

Measurements of hohlraum-produced fast ions

2019-04-12T21:54:52Z

Measurements of hohlraum-produced fast ions Zylstra, A.B.; Li, C.; Seguin, F.H.; Rosenberg, M.J.; Rinderknecht, H.G.; Sinenian, N.; Frenje, J.A.; Petrasso, R.D.; Izumi, N.; Amendt, P.A.; Landen, O.L.; Koch, J.A.

First Measurements of Rayleigh-Taylor-Induced Magnetic Fields in Laser-produced Plasmas

2019-04-12T21:54:51Z

First Measurements of Rayleigh-Taylor-Induced Magnetic Fields in Laser-produced Plasmas Manuel, M.J.; Li, C.K.; Seguin, F.H.; Frenje, J.; Casey, D.T.; Petrasso, R.D.; Hu, S.X.; Betti, R.; Hager, J.; Meyerhofer, D.D.; Smalyuk, V.

Mapping Return Currents in Laser-generated Z-pinch Plasmas

2019-04-12T21:54:52Z

Mapping Return Currents in Laser-generated Z-pinch Plasmas Manuel, M.J.; Sinenian, N.; Seguin, F.H.; Li, C.K.; Frenje, J.; Rinderknecht, H.G.; Casey, D.T.; Zylstra, A.B.; Petrasso, R.D.; Beg, F.N.

Surface thermocouples for measurement of pulsed heat flux in the divertor of the Alcator C-Mod tokamak

2019-04-12T21:54:50Z

Surface thermocouples for measurement of pulsed heat flux in the divertor of the Alcator C-Mod tokamak Brunner, D.; Bombard, B.

A multithreaded modular software toolkit for control of complex experiments

2019-04-10T09:18:57Z

A multithreaded modular software toolkit for control of complex experiments Sinenian, N.; Zylstra, A.B.; Manuel, M.J.; Frenje, J.A.; Kanojia, A.; Stillerman, J.; Petrasso, R.D.

Evidence for stratification of deuterium-tritium fuel in inertial confinement fusion implosions

2019-04-12T21:54:51Z

Evidence for stratification of deuterium-tritium fuel in inertial confinement fusion implosions Casey, D.T.; Frenje, J.A.; Johnson, M.; Manuel, M.J.; Rinderknecht, H.G.; Sinenian, N.; Seguin, F.H.; Li, C.K.; Petrasso, R.D.; Radha, P.B.; Delettrez, J.A.; Glebov, V.; Meyerhofer, D.D.; Sangster, T.C.; Nabb, D.P.; Amendt, P.A.; Boyd, R.N.; Rygg, J.R.; Herrmann, H.W.; Kim, Y.H.; Bacher, A.D.

The Third Omega Laser Facility Users’ Group Workshop

2019-04-12T21:54:51Z

The Third Omega Laser Facility Users’ Group Workshop Petrasso, R.D.

The response of CR-39 nuclear track detector to 1-9 MeV protons

2019-04-12T21:54:51Z

The response of CR-39 nuclear track detector to 1-9 MeV protons Sinenian, N.; Rosenberg, M.J.; Manuel, M.J.; Duffee, S.C.; Casey, D.T.; Zylstra, A.B.; Rinderknecht, H.G.; Johnson, M.; Seguin, F.H.; Frenje, J.A.; Li, C.K.; Petrasso, R.D.

Feasibility Study for a Correlation Electron Cyclotron Emission Turbulence Diagnostic Based on Nonlinear Gyrokinetic Simulations

2019-04-12T21:54:50Z

Feasibility Study for a Correlation Electron Cyclotron Emission Turbulence Diagnostic Based on Nonlinear Gyrokinetic Simulations White, A.E.; Howard, N.T.; Mikkelsen, D.R.; Greenwald, M.; Candy, J.; Waltz, R.E.

Omnigenity as Generalized Quasisymmetry

2019-04-10T09:18:57Z

Omnigenity as Generalized Quasisymmetry Landreman, Matt; Catto, Peter

Electron Temperature Fluctuations Associated with the Weakly Coherent Mode in the Edge of I-mode Plasmas

2019-04-12T21:54:49Z

Electron Temperature Fluctuations Associated with the Weakly Coherent Mode in the Edge of I-mode Plasmas White, A.E.; Phillips, P.; Whyte, D.G.; Hubbard, A.E.; Sung, C.; Hughes, J.W.; Dominguez, A.; Terry, J.; Cziegler, I.

Neoclassical theory of pedestal flows and comparison with Alcator C-Mod measurements

2019-04-12T21:54:50Z

Neoclassical theory of pedestal flows and comparison with Alcator C-Mod measurements Kagan, Grigory; Marr, Kenneth; Pusztai, Istvan; Landreman, Matt; Catto, Peter; Lipschultz, Bruce

Variational Calculation of Neoclassical Ion Heat Flux in the Banana Regime for Axisymmetric Magnetic Geometry

2019-04-12T21:54:50Z

Variational Calculation of Neoclassical Ion Heat Flux in the Banana Regime for Axisymmetric Magnetic Geometry Parker, J.B.; Catto, P.J.

Interaction of Charged Particles with Localized Electrostatic Waves in a Magnetized Plasma

2019-04-12T21:54:50Z

Interaction of Charged Particles with Localized Electrostatic Waves in a Magnetized Plasma Kominis, Y.; Ram, A.K.; Hizanidis, K.

Production of internal transport barriers via self-generated mean flows in Alcator C-Mod

2019-04-10T09:18:56Z

Production of internal transport barriers via self-generated mean flows in Alcator C-Mod Fiore, C.L.; Ernst, D.R.; Podpaly, Y.A.; Mikkelsen, D.; Howard, N.T.; Lee, Jungpyo; Reinke, M.L.; Rice, J.E.; Hughes, J.W.; Ma, Y.; Rowan, W.L.; Bespamyatnov, I.

H-mode power threshold reduction in a slot divertor configuration on the Alcator C-Mod tokamak

2019-04-10T09:18:56Z

H-mode power threshold reduction in a slot divertor configuration on the Alcator C-Mod tokamak Ma, Y.; Hughes, J.W.; Hubbard, A.E.; Bombard, B.; Terry, J.

Characterization of the Pedestal in Alcator C-Mod ELMing H-Modes and Comparison to the EPED Model

2019-04-12T21:54:49Z

Characterization of the Pedestal in Alcator C-Mod ELMing H-Modes and Comparison to the EPED Model Walk, J.R.; Snyder, P.B.; Hughes, J.W.; Terry, J.L.; Hubbard, A.E.; Phillips, P.

Lower hybrid current drive at high density in the multi-pass regime

2019-04-12T21:54:49Z

Lower hybrid current drive at high density in the multi-pass regime Wallace, G.M.; Faust, I.C.; Meneghini, O.; Parker, R.R.; Shiraiwa, S.; Baek, S.G.; Bonoli, P.T.; Hubbard, A.E.; Hughes, J.W.; Bombard, B.L.; Lau, C.; Ma, Y.; Reinke, M.L.; Schmidt, A.E.; Terry, J.L.; Whyte, D.G.; Wright, J.C.; Wukitch, S.J.; Harvey, R.W.; Smirnov, A.P.; Wilson, J.R.

Co- and Counter-current Rotation Induced by Lower Hybrid Current Drive in Tokamak Plasmas

2019-04-12T21:54:49Z

Co- and Counter-current Rotation Induced by Lower Hybrid Current Drive in Tokamak Plasmas Podpaly, Y.A.; Rice, J.; Parker, R.; Reinke, M.; Shiraiwa, S.; Aparicio, L.; Scott, S.; Ennever, P.; Gao, C.; Irby, J.; Lee, J.; Meneghini, O.; Mumgaard, R.; Porkolab, M.; Tsujii, N.; Walk, J.; Wallace, G.

Steady I-mode Plasmas in Alcator C-Mod

2019-04-12T21:54:49Z

Steady I-mode Plasmas in Alcator C-Mod Marmar, E.S.; Dominguez, A.; Greenwald, M.J.; Howard, N.; Hubbard, A.E.; Hughes, J.W.; Kessel, C.; Bombard, B.; Lipschultz, B.; Reinke, M.L.; Rice, J.E.; Snyder, P.B.; Terry, J.L.; White, A.E.; Whyte, D.G.

Effects of thermal expansion of crystal-lattice on x-ray imaging crystal spectrometers

2019-04-12T21:54:48Z

Effects of thermal expansion of crystal-lattice on x-ray imaging crystal spectrometers Aparicio, L.; Bitter, M.; Podpaly, Y.; Rice, J.; Burke, W.; Rio, M.; Hill, K.; Pablant, N.; Beiersdorfer, P.; Bell, R.; Feder, R.; Gao, C.; Johnson, D.; Lee, S.G.; Marmar, E.; Reinke, M.L.; Scott, S.; Wilson, R.

Use of inductive heating for superconducting magnet protection

2019-04-10T09:18:56Z

Use of inductive heating for superconducting magnet protection Bromberg, L.; Minervini, J.V.; Schultz, J.H.; Antaya, T.; Myatt, L.

Millimeter-Wave Heating, Radiometry, and Calorimetry of Granite Rock to Vaporization

2019-04-12T21:54:48Z

Millimeter-Wave Heating, Radiometry, and Calorimetry of Granite Rock to Vaporization Woskov, Paul; Michael, Phil

Ohmic Energy Confinement Saturation and Core Toroidal Rotation Reversal in Alcator C-Mod Plasmas

2019-04-12T21:54:48Z

Ohmic Energy Confinement Saturation and Core Toroidal Rotation Reversal in Alcator C-Mod Plasmas Rice, J.E.; Greenwald, M.J.; Podpaly, Y.A.; Reinke, M.L.; Diamond, P.H.; Hughes, J.W.; Howard, N.T.; Ma, Y.; Cziegler, I.; Duval, B.P.; Ennever, P.C.; Ernst, D.; Fiore, C.L.; Gao, C.; Irby, J.H.; Marmar, E.S.; Porkolab, M.; Tsujii, N.; Wolfe, S.M.

Changes in CR‐39 proton sensitivity due to prolonged exposure to high vacuums relevant to the National Ignition Facility and OMEGA

2019-04-12T21:54:48Z

Changes in CR‐39 proton sensitivity due to prolonged exposure to high vacuums relevant to the National Ignition Facility and OMEGA Manuel, M.J.; Rosenberg, M.J.; Sinenian, N.; Rinderknecht, H.; Zylstra, A.B.; Seguin, F.H.; Frenje, J.; Li, C.K.; Petrasso, R.D.

Measurements of the differential cross section for the elastic n-[superscript 3]H and n-[superscript 2]H scattering at 14.1 MeV by using an Inertial Confinement Fusion (ICF) facility

2019-04-10T23:59:51Z

Measurements of the differential cross section for the elastic n-[superscript 3]H and n-[superscript 2]H scattering at 14.1 MeV by using an Inertial Confinement Fusion (ICF) facility Frenje, J.A.; Li, C.K.; Seguin, F.H.; Casey, D.T.; Petrasso, R.D.; Nabb, D.P.; Navratil, P.; Quaglioni, S.; Sangster, T.C.; Glebov, V.; Meyerhofer, D.D.

Scaling of H-mode threshold power and L-H edge conditions with favorable ion grad-B drift in Alcator C-Mod tokamak

2019-04-10T09:18:55Z

Scaling of H-mode threshold power and L-H edge conditions with favorable ion grad-B drift in Alcator C-Mod tokamak Ma, Y.; Hughes, J.W.; Hubbard, A.E.; Bombard, B.; Churchill, R.M.; Golfinopolous, T.; Tsujii, N.; Marmar, E.S.

Electron Velocity Distribution Instability in Magnetized Plasma Wakes and Artificial Electron Mass

2019-04-12T21:54:47Z

Electron Velocity Distribution Instability in Magnetized Plasma Wakes and Artificial Electron Mass Hutchinson, I.H.

Impurity Flows and Plateau-Regime Poloidal Density Variation in a Tokamak Pedestal

2019-04-10T07:33:57Z

Impurity Flows and Plateau-Regime Poloidal Density Variation in a Tokamak Pedestal Landreman, M.; Fulop, T.; Guszejnov, D.

Multi machine scaling of fuel retention in 4 carbon dominated tokamaks

2019-04-12T21:54:45Z

Multi machine scaling of fuel retention in 4 carbon dominated tokamaks Tsitrone, E.; Pegourie, B.; Marandet, Y.; Artaud, J.F.; Brosset, C.; Bucalossi, J.; Corre, Y.; Dittmar, T.; Gauthier, E.; Languille, P.; Linez, F.; Loarer, T.; Martin, C.; Roubin, P.; Kallenbach, A.; Krieger, K.; Mayer, M.; Neu, R.; Rohde, V.; Roth, J.; Rubel, M.; Brezinsek, S.; Kirschner, A.; Kreter, A.; Litnovsky, A.; Philipps, V.; Wienhold, P.; Likonen, J.; Coad, P.; Lipschultz, B.; Doerner, R.

The scaling of fuel recovered following un-mitigated disruptions in Alcator C-Mod with high-Z PFCs

2019-04-10T23:59:51Z

The scaling of fuel recovered following un-mitigated disruptions in Alcator C-Mod with high-Z PFCs Lipschultz, B.; Whyte, D.G.; Granetz, R.S.; Loarte, A.; Reinke, M.L.; Wolfe, S.M.

Using laser-generated energetic protons for intertial confinement fusion radiography

2019-04-10T20:37:20Z

Using laser-generated energetic protons for intertial confinement fusion radiography Zylstra, A.B.; Li, C.K.; Rinderknecht, H.G.; Seguin, F.H.; Petrasso, R.D.

Poloidal variation of high-Z impurity density due to hydrogen minority ICRH on Alcator C-Mod

2019-04-09T16:39:55Z

Poloidal variation of high-Z impurity density due to hydrogen minority ICRH on Alcator C-Mod Reinke, M.L.; Hutchinson, I.H.; Rice, J.E.; Howard, N.T.; Bader, A.; Wukitch, S.; Lin, Y.; Pace, D.; Hubbard, A.; Hughes, J.W.; Podpaly, Y.

Analysis of C-MOD molybdenum divertor erosion and code/data comparison

2019-04-12T21:54:46Z

Analysis of C-MOD molybdenum divertor erosion and code/data comparison Brooks, J.N.; Allain, J.P.; Whyte, D.G.; Ochoukov, R.; Lipschultz, B.

Fluid and Drift-Kinetic Description of a Magnetized Plasma with Low Collisionality and Slow Dynamics Orderings. II: Ion Theory

2019-04-10T19:56:09Z

Fluid and Drift-Kinetic Description of a Magnetized Plasma with Low Collisionality and Slow Dynamics Orderings. II: Ion Theory Ramos, J.J.

The Coincidence Counting Technique for orders of magnitude background reduction in data obtained with the Magnetic Recoil Spectrometer at OMEGA and the NIF

2019-04-10T23:59:50Z

The Coincidence Counting Technique for orders of magnitude background reduction in data obtained with the Magnetic Recoil Spectrometer at OMEGA and the NIF Casey, D.T.; Frenje, J.A.; Seguin, F.H.; Li, C.K.; Rosenberg, M.J.; Rinderknecht, H.; Manuel, M.J.; Johnson, M.; Schaeffer, J.C.; Frankel, R.; Sinenian, N.; Childs, R.A.; Petrasso, R.D.

Investigation of lower hybrid physics through power modulation experiments on Alcator C-Mod

2019-04-10T23:59:51Z

Investigation of lower hybrid physics through power modulation experiments on Alcator C-Mod Schmidt, A.E.; Bonoli, P.T.; Meneghini, O.; Parker, R.R.; Porkolab, M.; Shiraiwa, S.; Wallace, G.M.; Wright, J.C.; Harvey, R.W.; Wilson, J.R.

Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak Ohmic L-mode Plasmas

2019-04-09T17:39:01Z

Rotation Reversal Bifurcation and Energy Confinement Saturation in Tokamak Ohmic L-mode Plasmas Rice, J.E.; Cziegler, I.; Diamond, P.H.; Duval, B.P.; Podpaly, Y.A.; Reinke, M.L.; Ennever, P.C.; Greenwald, M.J.; Hughes, J.W.; Ma, Y.; Marmar, E.S.; Tsujii, N.; Wolfe, S.M.

HTS Twisted Stacked-Tape Cable Development

2019-04-10T23:59:36Z

HTS Twisted Stacked-Tape Cable Development Takayasu, Makoto; Minervini, Joseph; Bromberg, Leslie

Forces on a spherical conducting particle in ExB fields

2019-04-12T21:54:13Z

Forces on a spherical conducting particle in ExB fields Patacchini, L.; Hutchinson, I.H.

Investigations of HTS Twisted Stacked-Tape Conductor

2019-04-10T23:59:50Z

Investigations of HTS Twisted Stacked-Tape Conductor Takayasu, Makoto; Chiesa, Luisa; Bromberg, Leslie; Minervini, Joseph

Fluctuation Driven Transport and Stationary Profiles

2019-04-10T23:59:50Z

Fluctuation Driven Transport and Stationary Profiles Kesner, J.; Garnier, D.T.; Mauel, M.E.

Forces on a Small Grain in the Nonlinear Plasma Wake of Another

2019-04-12T21:54:45Z

Forces on a Small Grain in the Nonlinear Plasma Wake of Another Hutchinson, I.H.

Increasing the energy dynamic range of solid-state nuclear track detectors using multiple surfaces

2019-04-12T21:54:45Z

Increasing the energy dynamic range of solid-state nuclear track detectors using multiple surfaces Zylstra, A.B.; Rinderknecht, H.G.; Sinenian, N.; Rosenberg, M.J.; Manuel, M.; Seguin, F.H.; Casey, D.T.; Frenje, J.A.; Li, C.K.; Petrasso, R.D.

Observations of Core Toroidal Rotation Reversals in Alcator C-Mod Ohmic L-mode Plasmas

2019-04-10T23:59:48Z

Observations of Core Toroidal Rotation Reversals in Alcator C-Mod Ohmic L-mode Plasmas Rice, J.E.; Duval, B.P.; Reinke, M.L.; Podpaly, Y.A.; Bortolon, A.; Churchill, R.M.; Cziegler, I.; Diamond, P.H.; Dominguez, A.; Ennever, P.C.; Fiore, C.L.; Granetz, R.S.; Greenwald, M.J.; Hubbard, A.E.; Hughes, J.W.; Irby, J.H.; Ma, Y.; Marmar, E.S.; Dermott, R.M.; Porkolab, M.; Tsujii, N.; Wolfe, S.M.

Configurable DC current leads, with Peltier elements

2019-04-12T21:54:45Z

Configurable DC current leads, with Peltier elements Bromberg, L.; Michael, P.; Takayasu, M.; Minervini, J.V.

A study of tungsten migration in the Alcator C-Mod divertor

2019-04-12T21:54:45Z

A study of tungsten migration in the Alcator C-Mod divertor Barnard, H.S.; Lipschultz, B.; Whyte, D.G.

Tungsten Measurement on Alcator C-Mod and EBIT for Future Fusion Reactors

2019-04-12T21:54:17Z

Tungsten Measurement on Alcator C-Mod and EBIT for Future Fusion Reactors Podpaly, Y.A.; Rice, J.E.; Beiersdorfer, P.; Reinke, M.; Clementson, J.; Barnard, H.S.

Probing high areal-density (ρR) cryogenic DT implosions using down scattered neutron spectra measured by the Magnetic Recoil Spectrometer (MRS)

2019-04-10T21:12:01Z

Probing high areal-density (ρR) cryogenic DT implosions using down scattered neutron spectra measured by the Magnetic Recoil Spectrometer (MRS) Frenje, J.A.; Casey, D.T.; Li, C.K.; Seguin, F.H.; Petrasso, R.D.; Glebov, V.; Radha, P.B.; Sangster, T.C.; Meyerhofer, D.D.; Hatchett, S.P.; Haan, S.W.; Cerjan, C.J.; Landen, O.L.; Fletcher, K.A.; Leeper, R.J.

The Second Omega Laser Facility Users' Group Workshop 28 April - 1 May 2010

2019-04-10T23:59:48Z

The Second Omega Laser Facility Users' Group Workshop 28 April - 1 May 2010 Petrasso, R.D.

Highly Portable Continuous Plasma Separator for Whole Blood

2019-04-10T23:59:48Z

Highly Portable Continuous Plasma Separator for Whole Blood Takayasu, M.; Ash, S.R.

Loss Estimate for ITER ECH Transmission Line Including Multimode Propagation

2019-04-12T21:54:16Z

Loss Estimate for ITER ECH Transmission Line Including Multimode Propagation Shapiro, M.A.; Kowalski, E.J.; Sirigiri, J.R.; Tax, D.S.; Temkin, R.J.; Bigelow, T.S.; Caughman, J.B.; Rasmussen, D.A.

Measurement of wakefields in a 17 GHz photonic bandgap accelerator structure

2019-04-10T23:59:41Z

Measurement of wakefields in a 17 GHz photonic bandgap accelerator structure Marsh, R.A.; Shapiro, M.A.; Temkin, R.J.; Smirnova, E.I.; Ford, J.F.

Operation of a Continuously Frequency-Tunable Second-Harmonic CW 330-GHz Gyrotron for Dynamic Nuclear Polarization

2019-04-09T19:12:56Z

Operation of a Continuously Frequency-Tunable Second-Harmonic CW 330-GHz Gyrotron for Dynamic Nuclear Polarization Torrezan, A.C.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.; Griffin, R.G.

Continuous-Wave Operation of a Frequency Tunable 460 GHz Second-Harmonic Gyrotron for Enhanced Nuclear Magnetic Resonance

2019-04-10T23:59:40Z

Continuous-Wave Operation of a Frequency Tunable 460 GHz Second-Harmonic Gyrotron for Enhanced Nuclear Magnetic Resonance Torrezan, A.C.; Han, S.T.; Mastovsky, I.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.; Barnes, A.B.; Griffin, R.G.

Experimental Results on a 1.5 MW, 110 GHz Gyrotron with a Smooth Mirror Mode Converter

2019-04-12T21:54:16Z

Experimental Results on a 1.5 MW, 110 GHz Gyrotron with a Smooth Mirror Mode Converter Tax, D.S.; Choi, E.M.; Mastovsky, I.; Neilson, J.M.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.; Torrezan, A.C.

Calculation of a Hyperbolic Corrugated Horn Converting the TEM00 Mode to the HE[subscript 11] Mode

2019-04-09T15:35:31Z

Calculation of a Hyperbolic Corrugated Horn Converting the TEM00 Mode to the HE[subscript 11] Mode Shapiro, M.A.; Temkin, R.J.

X-band photonic band-gap accelerator structure breakdown experiment

2019-04-10T23:59:40Z

X-band photonic band-gap accelerator structure breakdown experiment Marsh, R.A.; Temkin, R.J.; Dolgashev, V.A.; Laurent, L.L.; Lewandowski, J.R.; Yeremian, A.D.; Tantawi, S.G.

Amplification of Picosecond Pulses in a 140-GHz Gyrotron-Traveling Wave Tube

2019-04-10T23:59:40Z

Amplification of Picosecond Pulses in a 140-GHz Gyrotron-Traveling Wave Tube Kim, H.J.; Nanni, E.A.; Shapiro, M.A.; Sirigiri, J.R.; Woskov, P.P.; Temkin, R.J.

Linearly Polarized Modes of a Corrugated Metallic Waveguide

2019-04-10T23:59:40Z

Linearly Polarized Modes of a Corrugated Metallic Waveguide Kowalski, E.J.; Tax, D.S.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.; Bigelow, T.S.; Rasmussen, D.A.

Edge energy transport barrier and turbulence in the I-mode regime on Alcator C-Mod

2019-04-12T21:54:16Z

Edge energy transport barrier and turbulence in the I-mode regime on Alcator C-Mod Hubbard, A.; Whyte, D.G.; Churchill, R.M.; Cziegler, I.; Dominguez, A.; Golfinopoulos, T.; Hughes, J.W.; Rice, J.E.; Bespamyatnov, I.; Greenwald, M.; Howard, N.; Lipschultz, B.; Marmar, E.S.; Reinke, M.L.; Rowan, W.L.; Terry, J.L.

Scaling of the power exhaust channel in Alcator C-Mod

2019-04-10T23:59:39Z

Scaling of the power exhaust channel in Alcator C-Mod Bombard, B.; Terry, J.L.; Hughes, J.W.; Brunner, D.; Payne, J.; Reinke, M.L.; Cziegler, I.; Granetz, R.; Greenwald, M.; Hutchinson, I.H.; Irby, J.; Lin, Y.; Lipschultz, B.; Ma, Y.; Marmar, E.S.; Rowan, W.L.; Tsujii, N.; Wallace, G.; Whyte, D.G.; Wolfe, S.; Wukitch, S.; Wurden, G.

Pressure Dependence of Plasma Structure in Microwave Gas Breakdown at 110 GHz

2019-04-10T23:59:39Z

Pressure Dependence of Plasma Structure in Microwave Gas Breakdown at 110 GHz Cook, A.; Shapiro, M.; Temkin, R.

Sources of intrinsic rotation in the low flow ordering

2019-04-12T21:54:15Z

Sources of intrinsic rotation in the low flow ordering Parra, Felix; Barnes, Michael; Catto, Peter

High confinement/high radiated power H-mode experiments in Alcator C-Mod and consequences for ITER Q[subscript DT] = 10 operation

2019-04-10T23:59:39Z

High confinement/high radiated power H-mode experiments in Alcator C-Mod and consequences for ITER Q[subscript DT] = 10 operation Loarte, A.; Hughes, J.W.; Reinke, M.L.; Terry, J.L.; Bombard, B.; Brunner, D.; Greenwald, M.; Lipschultz, B.; Ma, Y.; Wukitch, S.J.; Wolfe, S.

Power requirements for superior H-mode confinement on Alcator C-Mod: Experiments in support of ITER

2019-04-12T21:54:15Z

Power requirements for superior H-mode confinement on Alcator C-Mod: Experiments in support of ITER Hughes, J.W.; Loarte, A.; Reinke, M.L.; Terry, J.L.; Brunner, D.; Greenwald, M.; Hubbard, A.E.; Bombard, B.; Lipschultz, B.; Ma, Y.; Wolfe, S.; Wukitch, S.J.

Lower Hybrid Current Drive at High Density in Alcator C-Mod

2019-04-12T21:54:16Z

Lower Hybrid Current Drive at High Density in Alcator C-Mod Wallace, G.M.; Hubbard, A.E.; Bonoli, P.T.; Faust, I.C.; Harvey, R.W.; Hughes, J.W.; Bombard, B.L.; Meneghini, O.; Parker, R.R.; Schmidt, A.E.; Shiraiwa, S.; Smirnov, A.P.; Whyte, D.G.; Wilson, J.R.; Wright, J.C.; Wukitch, S.J.

ICRF Mode Conversion Flow Drive on Alcator C-Mod

2019-04-10T23:59:38Z

ICRF Mode Conversion Flow Drive on Alcator C-Mod Lin, Y.; Rice, J.E.; Wukitch, S.J.; Reinke, M.L.; Greenwald, M.J.; Hubbard, A.E.; Marmar, E.S.; Podpaly, Y.; Porkolab, M.; Tsujii, N.

Geometry and neoclassial theory in a quasi-isodynamic stellarator

2019-04-10T23:59:37Z

Geometry and neoclassial theory in a quasi-isodynamic stellarator Landreman, Matt; Catto, Peter

Radial Electric Field Evaluation and Effects in the Core and Pedestal

2019-04-12T21:54:15Z

Radial Electric Field Evaluation and Effects in the Core and Pedestal Catto, Peter; Parra, Felix; Kagan, Grigory; Landreman, Matt

Pure-Bending Strain Investigations: Device and ITER Nb [subscript 3]Sn Wires

2019-04-12T21:54:15Z

Pure-Bending Strain Investigations: Device and ITER Nb [subscript 3]Sn Wires Takayasu, M.; Chiesa, L.; Harris, D.L.; Allegritti, A.; Minervini, J.V.

Spherical conducting probes in finite Debye length plasmas and ExB fields

2019-04-12T21:54:15Z

Spherical conducting probes in finite Debye length plasmas and ExB fields Patacchini, L.; Hutchinson, I.H.

Stellarator Configuration Improvement Using High Temperature Superconducting Monoliths

2019-04-10T23:59:37Z

Stellarator Configuration Improvement Using High Temperature Superconducting Monoliths Bromberg, L.; Meneghini, O.; Minervini, J.V.; Brown, T.; Heitzenroeder, P.; Neilson, G.H.; Zarnstorff, M.; Boozer, A.

Thermal Analysis of Graphite and Silicon Carbide with Millimeter-Wave Radiometry

2019-04-10T23:59:37Z

Thermal Analysis of Graphite and Silicon Carbide with Millimeter-Wave Radiometry Woskov, P.P.; Sundaram, S.K.

Status of High Temperature Superconducting Magnet Development

2019-04-12T21:54:14Z

Status of High Temperature Superconducting Magnet Development Bromberg, L.; Hashizume, H.; Ito, S.; Minervini, J.V.; Yanagi, N.

A unified treatment of kinetic effects in a tokamak pedestal

2019-04-12T21:54:13Z

A unified treatment of kinetic effects in a tokamak pedestal Catto, Peter; Kagan, Gregory; Landreman, Matt; Pusztai, Istvan

Heavy Duty Vehicles Using Clean, High Efficiency Alcohol Engines

2019-04-10T23:59:36Z

Heavy Duty Vehicles Using Clean, High Efficiency Alcohol Engines Bromberg, Leslie; Cohn, Daniel

Scattering of radio frequency waves by edge density blobs in tokamak plasmas

2019-04-12T21:54:12Z

Scattering of radio frequency waves by edge density blobs in tokamak plasmas Ram, A.K.; Hizanidis, K.; Kominis, Y.; Tsironis, C.

Dynamics of charged particles in spatially chaotic magnetic fields

2019-04-12T21:54:13Z

Dynamics of charged particles in spatially chaotic magnetic fields Ram, Abhay; Dasgupta, Brahmananda

Effects of the radial electric field in a quasisymmetric

2019-04-09T18:07:09Z

Effects of the radial electric field in a quasisymmetric Landreman, Matt; Catto, Peter

The Edge Temperature Gradient as Intrinsic Rotation Drive in Alcator C-Mod Tokamak Plasmas

2019-04-10T23:59:36Z

The Edge Temperature Gradient as Intrinsic Rotation Drive in Alcator C-Mod Tokamak Plasmas Rice, J.E.; Hughes, J.W.; Diamond, P.H.; Kosuga, Y.; Podpaly, Y.A.; Reinke, M.L.; Greenwald, M.J.; Gurcan, O.D.; Hahm, T.S.; Hubbard, A.E.; Marmar, E.S.; Devitt, C.J.; Whyte, D.G.

The effect of the radial electric field on neoclassical flows in a tokamak pedestal

2019-04-12T21:54:13Z

The effect of the radial electric field on neoclassical flows in a tokamak pedestal Kagan, Grigory; Marr, Kenneth; Catto, Peter; Landreman, Matt; Lipschultz, Bruce; Dermott, Rachael

Quasilinear theory revisited: General kinetic formulation of wave-particle interactions in plasmas

2019-04-12T21:54:12Z

Quasilinear theory revisited: General kinetic formulation of wave-particle interactions in plasmas Hizanidis, K.; Kominis, Y.; Ram, A.K.

Particle interactions with spatially localized wavepackets

2019-04-10T23:59:35Z

Particle interactions with spatially localized wavepackets Kominis, Y.; Hizanidis, K.; Ram, A.K.

Nonlinear heating of ions by electron cyclotron frequency waves

2019-04-10T21:03:17Z

Nonlinear heating of ions by electron cyclotron frequency waves Hizanidis, K.; Zestanakis, P.A.; Ram, A.K.; Kominis, Y.

Charged-Particle Probing of X-Ray-Driven Inertial-Fusion Implosions

2019-04-09T18:51:49Z

Charged-Particle Probing of X-Ray-Driven Inertial-Fusion Implosions Li, C.K.; Seguin, F.H.; Frenje, J.A.; Rosenberg, M.; Petrasso, R.D.; Amendt, P.A.; Koch, J.A.; Landen, O.L.; Park, H.S.; Robey, H.F.; Town, R.P.; Casner, A.; Philippe, F.; Betti, R.; Knauer, J.P.; Meyerhofer, D.D.; Back, T.A.; Kilkenny, J.D.; Nikroo, A.

Non-linear collisionless plasma wakes of small particles

2019-04-10T23:59:35Z

Non-linear collisionless plasma wakes of small particles Hutchinson, I.H.

Development of a Synthetic Phase Contrast Imaging Diagnostic

2019-04-10T07:20:37Z

Development of a Synthetic Phase Contrast Imaging Diagnostic Rost, J.; Lin, L.; Porkolab, M.

Diagnosing Indirect-Drive Inertial-Confinement-Fusion Implosions with Charged Particles

2019-04-10T23:59:46Z

Diagnosing Indirect-Drive Inertial-Confinement-Fusion Implosions with Charged Particles Li, C.K.; Seguin, F.H.; Frenje, J.A.; Rosenberg, M.; Petrasso, R.D.; Amendt, P.A.; Koch, J.A.; Landen, O.L.; Park, H.S.; Robey, H.F.; Town, R.P.; Casner, A.; Philippe, F.; Betti, R.; Knauer, J.P.; Meyerhofer, D.D.; Back, T.A.; Kilkenny, J.D.; Nikroo, A.

Transport of momentum in full f gyrokinetics

2019-04-12T21:54:12Z

Transport of momentum in full f gyrokinetics Parra, Felix; Catto, Peter

28 GHz Gyrotron ECRH on LDX

2019-04-12T21:54:12Z

28 GHz Gyrotron ECRH on LDX Woskov, P.P.; Kesner, J.; Michael, P.C.; Garnier, D.T.; Mauel, M.E.

Stationary density profiles in the levitated dipole experiment: towards fusion without tritium fuel

2019-04-10T23:59:34Z

Stationary density profiles in the levitated dipole experiment: towards fusion without tritium fuel Kesner, J.; Davis, M.S.; Ellsworth, J.L.; Garnier, D.T.; Kahn, J.; Mauel, M.E.; Michael, P.; Wilson, B.; Woskov, P.P.

Impeding hohlraum plasma stagnation in inertial-confinement fusion

2019-04-10T23:59:35Z

Impeding hohlraum plasma stagnation in inertial-confinement fusion Li, C.K.; Seguin, F.H.; Frenje, J.A.; Rosenberg, M.J.; Rinderknecht, H.G.; Zylstra, A.B.; Petrasso, R.D.; Amendt, P.A.; Landen, O.L.; Mackinnon, A.J.; Town, R.P.; Wilks, S.C.; Betti, R.; Meyerhofer, D.D.; Soures, J.M.; Hund, J.; Kilkeny, J.D.; Nikroo, A.

Strong Turbulent Pinch of Plasma Confined by a Levitated Dipole Magnet

2019-04-09T18:17:37Z

Strong Turbulent Pinch of Plasma Confined by a Levitated Dipole Magnet Boxer, A.C.; Bergmann, R.; Ellsworth, J.L.; Garnier, D.T.; Kesner, J.; Mauel, M.E.; Woskov, P.

MHD Stability Comparison Theorems Revisted

2019-04-12T21:54:12Z

MHD Stability Comparison Theorems Revisted Cerfon, Antoine; Freidberg, Jeffrey

Flowing plasmas and absorbing objects: analytic and numerical solutions culminating 80 years of ion collection theory

2019-04-09T16:53:44Z

Flowing plasmas and absorbing objects: analytic and numerical solutions culminating 80 years of ion collection theory Hutchinson, I.H.; Patacchini, L.

Effect of N[subscript 2], Ne and Ar seeding on Alcator C-Mod H-mode confinement

2019-04-09T18:10:30Z

Effect of N[subscript 2], Ne and Ar seeding on Alcator C-Mod H-mode confinement Reinke, M.L.; Hughes, J.W.; Loarte, A.; Brunner, D.; Hutchinson, I.H.; Bombard, B.; Payne, J.; Terry, J.L.

VUV Impurity Spectroscopy on the Alcator C-Mod Tokamak

2019-04-10T23:59:34Z

VUV Impurity Spectroscopy on the Alcator C-Mod Tokamak Reinke, M.L.; Beiersdorfer, P.; Howard, N.; Magee, E.W.; Podpaly, Y.; Rice, J.E.; Terry, J.L.

Divertor IR Thermography on Alcator C-Mod

2019-04-12T21:54:11Z

Divertor IR Thermography on Alcator C-Mod Terry, J.L.; Bombard, B.; Brunner, D.; Payne, J.; Wurden, G.A.

Using mixed gases for massive gas injection disruption mitigation on Alcator C-Mod

2019-04-12T21:54:11Z

Using mixed gases for massive gas injection disruption mitigation on Alcator C-Mod Bakhtiari, M.; Olynyk, G.; Granetz, R.; Whyte, D.G.; Reinke, M.L.; Zhurovich, K.; Izzo, V.

Divertor heat flux footprints in EDA H-mode discharges on Alcator C-Mod

2019-04-10T23:59:33Z

Divertor heat flux footprints in EDA H-mode discharges on Alcator C-Mod Bombard, B.; Terry, J.L.; Hughes, J.W.; Brunner, D.; Payne, J.; Reinke, M.L.; Lin, Y.; Wukitch, S.

Millimeter-Wave Radiometer Diagnostics of Harmonic Electron Cyclotron Emission in the Levitated Dipole Experiment (LDX)

2019-04-10T23:59:33Z

Millimeter-Wave Radiometer Diagnostics of Harmonic Electron Cyclotron Emission in the Levitated Dipole Experiment (LDX) Woskov, P.P.; Kesner, J.; Garnier, D.T.; Mauel, M.E.

Kinetic Theory for Distribution Functions of Wave-Particle Interactions in Plasmas

2019-04-10T23:59:33Z

Kinetic Theory for Distribution Functions of Wave-Particle Interactions in Plasmas Kominis, Y.; Ram, A.K.; Hizanidis, K.

I-mode: An H-mode Energy Confinement Regime with L-mode Particle Transport in Alcator C-Mod.

2019-04-10T23:59:34Z

I-mode: An H-mode Energy Confinement Regime with L-mode Particle Transport in Alcator C-Mod. Whyte, D.G.; Hubbard, A.E.; Hughes, J.W.; Lipschultz, B.; Rice, J.E.; Marmar, E.S.; Greenwald, M.; Cziegler, I.; Dominguez, A.; Golfinopoulos, T.; Howard, N.; Lin, L.; Dermott, R.M.; Porkolab, M.; Reinke, M.L.; Terry, J.; Tsujii, N.; Wolfe, S.; Wukitch, S.; Lin, Y.

Comparison of Heat Flux Measurements by IR Thermography and Probes in the Alcator C-Mod Divertor

2019-04-12T21:54:11Z

Comparison of Heat Flux Measurements by IR Thermography and Probes in the Alcator C-Mod Divertor Brunner, D.; Bombard, B.; Payne, J.; Terry, J.L.

Comparison of neoclassical predictions with measured flows and evaluation of a poloidal impurity density asymmetry

2019-04-12T21:54:09Z

Comparison of neoclassical predictions with measured flows and evaluation of a poloidal impurity density asymmetry Marr, K.M.; Lipschultz, B.; Catto, P.J.; Reinke, M.L.; Simakov, A.N.

A versatile parallel block-tridiagonal solver for spectral codes

2019-04-12T21:54:09Z

A versatile parallel block-tridiagonal solver for spectral codes Lee, Jungpyo; Wright, John

The Ar[sup17+] Ly[sub alpha 2]/Ly[sub alpha 1] Ratio in Alcator C-Mod Tokamak Plasmas

2019-04-10T23:59:33Z

The Ar[sup17+] Ly[sub alpha 2]/Ly[sub alpha 1] Ratio in Alcator C-Mod Tokamak Plasmas Rice, J.E.; Reinke, M.L.; Ashbourn, J.M.; Cushman, A.C.; Podpaly, Y.A.; Gu, M.F.; Bitter, M.; Hill, K.; Rachlew, E.

Absorption of lower hybrid waves in the scrape off layer of a diverted tokamak

2019-04-12T21:54:10Z

Absorption of lower hybrid waves in the scrape off layer of a diverted tokamak Wallace, G.M.; Parker, R.R.; Bonoli, P.T.; Harvey, R.W.; Hubbard, A.E.; Hughes, J.W.; Bombard, B.L.; Meneghini, O.; Schmidt, A.E.; Shiraiwa, S.; Smirnov, A.P.; Whyte, D.G.; Wilson, J.R.; Wright, J.C.; Wukitch, S.J.

Parameter Scalings of ICRF Mode Conversion Flow Drive in Alcator C-Mod Plasmas

2019-04-09T17:23:43Z

Parameter Scalings of ICRF Mode Conversion Flow Drive in Alcator C-Mod Plasmas Rice, J.E.; Lin, Y.; Wukitch, S.J.; Podpaly, Y.; Reinke, M.L.

Neoclassical Plateau Regime Transport in a Tokamak Pedestal

2019-04-12T21:54:44Z

Neoclassical Plateau Regime Transport in a Tokamak Pedestal Pusztai, Istvan; Catto, Peter

Current redistribution in HTS cables made from 2nd generation tapes

2019-04-10T23:59:47Z

Current redistribution in HTS cables made from 2nd generation tapes Bromberg, L.; Takayasu, M.; Michael, P.

Evaluation of turbo-Brayton cycle for cooling current leads: Integrated current lead/heat exchanger

2019-04-12T21:54:44Z

Evaluation of turbo-Brayton cycle for cooling current leads: Integrated current lead/heat exchanger Bromberg, L.; Michael, P.

Fluid and Drift-Kinetic Description of a Magnetized Plasma with Low Collisionality and Slow Dynamics Orderings. I: Electron Theory

2019-04-12T21:54:44Z

Fluid and Drift-Kinetic Description of a Magnetized Plasma with Low Collisionality and Slow Dynamics Orderings. I: Electron Theory Ramos, J.J.

Trajectories, orbit squeezing, and residual zonal flow in a tokamak pedestal

2019-04-12T21:54:44Z

Trajectories, orbit squeezing, and residual zonal flow in a tokamak pedestal Landreman, Matt; Catto, Peter

Enhancement of the Bootstrap Current in a Tokamak Pedestal

2019-04-12T21:54:44Z

Enhancement of the Bootstrap Current in a Tokamak Pedestal Kagan, Grigory; Catto, P.J.

The Omega Laser Facility Users Group Workshop 29 April - 1 May 2009

2019-04-09T16:35:04Z

The Omega Laser Facility Users Group Workshop 29 April - 1 May 2009 Petrasso, R.D.

Observation and Study of Low-Frequency Oscillations in a 1.5-MW 110-GHz Gyrotron

2019-04-11T00:38:22Z

Observation and Study of Low-Frequency Oscillations in a 1.5-MW 110-GHz Gyrotron Cerfon, A.J.; Choi, E.M.; Marchewka, C.D.; Mastovsky, I.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.

Rotation and Transport in Alcator C-Mod ITB Plasmas

2019-04-11T00:38:22Z

Rotation and Transport in Alcator C-Mod ITB Plasmas Fiore, C.L.; Rice, J.E.; Podpaly, Y.; Bespamyatnov, I.O.; Rowan, W.L.; Hughes, J.W.; Reinke, M.

Demonstration of a 140-GHz 1-kW Confocal Gyro-Traveling-Wave Amplifier

2019-04-11T00:38:22Z

Demonstration of a 140-GHz 1-kW Confocal Gyro-Traveling-Wave Amplifier Joye, C.D.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.

Medical Cyclotrons

2019-04-11T00:38:25Z

Medical Cyclotrons Friesel, D.L.; Antaya, T.A.

Experimental Studies of Edge Turbulence and Confinement in Alcator C-Mod

2019-04-11T00:38:26Z

Experimental Studies of Edge Turbulence and Confinement in Alcator C-Mod Cziegler, I.; Terry, J.L.; Hughes, J.W.; Bombard, B.

Plasma structures observed in gas breakdown using a 1.5 MW, 110 GHz pulsed gyrotron

2019-04-12T14:47:44Z

Plasma structures observed in gas breakdown using a 1.5 MW, 110 GHz pulsed gyrotron Hidaka, Y.; Choi, E.M.; Mastovsky, I.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.; Edmiston, G.F.; Neuber, A.A.; Oda, Y.

Electron Transport by Radio Frequency Waves in Tokamaks

2019-04-11T00:38:25Z

Electron Transport by Radio Frequency Waves in Tokamaks Ram, A.K.; Kominis, Y.; Hizanidis, K.

Kinetic Theory for Distribution Functions of non-Markovian Wave-Particle Interactions in Plasmas

2019-04-11T00:38:25Z

Kinetic Theory for Distribution Functions of non-Markovian Wave-Particle Interactions in Plasmas Kominis, Y.; Ram, A.K.; Hizanidis, K.

Tutorial: Verification and Validation for Magnetic Fusion

2019-04-12T14:47:46Z

Tutorial: Verification and Validation for Magnetic Fusion Greenwald, M.

Hyperconducting joints using HTS powders

2019-04-12T14:47:46Z

Hyperconducting joints using HTS powders Bromberg, L.; Michael, P.

Estimates of DI Hydrous Ethanol Utilization for Knock Avoidance and Comparison to a Measured and Simulated DI E85 Baseline

2019-04-09T15:26:59Z

Estimates of DI Hydrous Ethanol Utilization for Knock Avoidance and Comparison to a Measured and Simulated DI E85 Baseline Bromberg, L.; Blumberg, P.

Fokker-Planck description of the scattering of radio frequency waves at the plasma edge

2019-04-12T14:47:46Z

Fokker-Planck description of the scattering of radio frequency waves at the plasma edge Hizanidis, K.; Ram, A.K.; Kominis, Y.; Tsironis, C.

Kinetic Effects in the Pedestal of a Tokamak

2019-04-11T00:38:23Z

Kinetic Effects in the Pedestal of a Tokamak Kagan, Grigory; Catto, P.J.

Neoclassical Ion Heat Flux and Poloidal Flow in a Tokamak Pedestal

2019-04-11T00:38:24Z

Neoclassical Ion Heat Flux and Poloidal Flow in a Tokamak Pedestal Kagan, Grigory; Catto, P.J.

Alcohol Fueled Heavy Duty Vehicles Using Clean, High Efficiency Engines

2019-04-12T14:47:46Z

Alcohol Fueled Heavy Duty Vehicles Using Clean, High Efficiency Engines Bromberg, L.; Cohn, D.R.

Non-physical momentum sources in slab geometry gyrokinetics

2019-04-12T14:47:46Z

Non-physical momentum sources in slab geometry gyrokinetics Catto, Peter

Modification of H-mode pedestal structure with lower hybrid waves on Alcator C‑Mod

2019-04-11T00:38:23Z

Modification of H-mode pedestal structure with lower hybrid waves on Alcator C‑Mod Hughes, J.W.; Hubbard, A.E.; Wallace, G.; Greenwald, M.; Bombard, B.; Lin, L.; Dermott, R.M.; Parker, R.R.; Reinke, M.L.; Rice, J.E.; Wilson, J.R.

Current Lead Optimization for Cryogenic Operation at Intermediate Temperatures

2019-04-12T14:47:45Z

Current Lead Optimization for Cryogenic Operation at Intermediate Temperatures Bromberg, L.; Michael, P.C.; Minervini, J.V.; Miles, C.

Spherical probes at ion saturation in ExB fields

2019-04-12T14:47:45Z

Spherical probes at ion saturation in ExB fields Patacchini, L.; Hutchinson, I.H.

Turbulent transport of toroidal angular momentum in low flow gyrokinetics

2019-04-12T14:47:45Z

Turbulent transport of toroidal angular momentum in low flow gyrokinetics Catto, Peter

Kinetic solution to the Mach probe problem in transversely flowing strongly magnetized plasmas

2019-04-12T14:47:45Z

Kinetic solution to the Mach probe problem in transversely flowing strongly magnetized plasmas Patacchini, L.; Hutchinson, I.H.

Coolant topology options for high temperature superconducting transmission and distribution systems

2019-04-12T14:47:45Z

Coolant topology options for high temperature superconducting transmission and distribution systems Bromberg, L.; Michael, P.C.; Minervini, J.V.; Miles, C.

Feasibility Study for Employing High Temperature Superconductor in a Steady State Compact Stellarator-Based Reactor Design

2019-04-11T00:38:23Z

Feasibility Study for Employing High Temperature Superconductor in a Steady State Compact Stellarator-Based Reactor Design Bromberg, L.; Michael, P.; Minervini, J.V.; Schultz, J.H.

Magnetic Field Shaping Using High Temperature Superconducting Monoliths

2019-04-11T00:38:23Z

Magnetic Field Shaping Using High Temperature Superconducting Monoliths Bromberg, L.; Minervini, J.V.; Schultz, J.H.; Boozer, A.; Brown, T.; Heitzenroeder, P.; Zarnstorff, M.

An assessment of full wave effects on the propagation and absorption of lower hybrid waves

2019-04-12T21:45:17Z

An assessment of full wave effects on the propagation and absorption of lower hybrid waves Wright, J.C.; Bonoli, P.T.; Schmidt, A.E.; Phillips, C.K.; Valeo, E.J.; Harvey, R.W.; Brambilla, M.A.

New Alcator C-MOD Rotated 10[degrees] 4-strap ICRF Antenna

2019-04-10T13:16:00Z

New Alcator C-MOD Rotated 10[degrees] 4-strap ICRF Antenna Koert, P.; Wukitch, S.J.; Beck, W.K.; Lin, Y.; Doody, J.; Mucic, N.P.

Localized measurement of short wavelength plasma fluctuations with the DIII-D phase contrast imaging diagnostic

2019-04-12T21:45:16Z

Localized measurement of short wavelength plasma fluctuations with the DIII-D phase contrast imaging diagnostic Dorris, J.R.; Rost, J.C.; Porkolab, M.

Comment on: "On higher order corrections to gyrokinetic Vlasov–Poisson equations in the long wavelength limit" [Ref. W.W. Lee et al., Phys. Plasmas 16, 044506 (2009)]

2019-04-12T21:45:16Z

Comment on: "On higher order corrections to gyrokinetic Vlasov–Poisson equations in the long wavelength limit" [Ref. W.W. Lee et al., Phys. Plasmas 16, 044506 (2009)] Parra, Felix; Catto, Peter

Upgrade of the ICRF Fault and Control Systems On Alcator C-Mod

2019-04-12T21:45:17Z

Upgrade of the ICRF Fault and Control Systems On Alcator C-Mod Murray, R.A.; Kanojia, A.; Burke, W.; Terry, D.; Binus, A.; Wukitch, S.; Lin, Y.; Parkin, B.

Full wave simulations of lower hybrid wave propagation in tokamaks

2019-04-12T21:45:17Z

Full wave simulations of lower hybrid wave propagation in tokamaks Wright, J.C.; Bonoli, P.T.; Phillips, C.K.; Valeo, E.; Harvey, R.W.

Limitations, Insights and Improvements to Gyrokinetics

2019-04-10T13:16:00Z

Limitations, Insights and Improvements to Gyrokinetics Catto, P.J.; Parra, F.I.; Kagan, G.; Simakov, A.N.

Continuum-plasma solution surrounding non-emitting spherical bodies

2019-04-10T13:16:00Z

Continuum-plasma solution surrounding non-emitting spherical bodies Patacchini, L.; Hutchinson, I.H.

Observations of Electromagnetic Fields and Plasma Flow in Hohlraums with proton Radiography

2019-04-10T13:16:00Z

Observations of Electromagnetic Fields and Plasma Flow in Hohlraums with proton Radiography Li, C.K.; Seguin, F.H.; Frenje, J.A.; Petrasso, R.D.; Amendt, P.A.; Town, R.P.; Landen, O.L.; Rygg, J.R.; Betti, R.; Knauer, J.P.; Meyerhofer, D.D.; Soures, J.M.; Back, C.A.; Kilkenny, J.D.; Nikroo, A.

Vorticity and Intrinsic Ambipolarity in Turbulent Tokamak

2019-04-09T17:53:46Z

Vorticity and Intrinsic Ambipolarity in Turbulent Tokamak Parra, F.I.; Catto, P.J.

Pfirsch-Schlüter Electric Field in a Tokamak

2019-04-12T21:45:16Z

Pfirsch-Schlüter Electric Field in a Tokamak Catto, P.J.; Simakov, A.N.

Pressure-driven, resistive instabilities in laser-produced high-energy-density plasmas

2019-04-09T15:37:46Z

Pressure-driven, resistive instabilities in laser-produced high-energy-density plasmas Li, C.K.; Frenje, J.A.; Petrasso, R.D.; Seguin, F.H.; Amendt, P.A.; Landen, O.L.; Town, R.P.; Betti, R.; Knauer, J.P.; Meyerhofer, D.; Soures, J.A.

Diagnosing fuel [rho]R and [rho]R asymmetries in cryogenic DT implosions using charged-particle spectrometry at OMEGA

2019-04-10T13:15:55Z

Diagnosing fuel [rho]R and [rho]R asymmetries in cryogenic DT implosions using charged-particle spectrometry at OMEGA Frenje, J.A.; Li, C.K.; Seguin, F.H.; Casey, D.T.; Petrasso, R.D.; Delettrez, J.; Yu, V.; Glebov, T.C.; Sangster, T.C.

Explicit time-reversible orbit integration in Particle In Cell codes with static homogeneous magnetic field

2019-04-10T13:15:55Z

Explicit time-reversible orbit integration in Particle In Cell codes with static homogeneous magnetic field Patacchini, L.; Hutchinson, I.H.

Alternate Form of Model Like Particle Collision Operator

2019-04-10T13:15:55Z

Alternate Form of Model Like Particle Collision Operator Catto, Peter; Ernst, Darin

Lorentz mapping of magnetic fields in hot, dense plasmas

2019-04-10T13:15:56Z

Lorentz mapping of magnetic fields in hot, dense plasmas Petrasso, R.D.; Li, C.K.; Seguin, F.H.; Rygg, J.R.; Frenje, J.A.; Betti, R.; Knauer, J.P.; Meyerhofer, D.D.; Amendt, P.A.; Froula, D.H.; Landen, O.L.; Patel, P.K.; Ross, J.S.; Town, R.P.

Gyrokinetic Equivalence

2019-04-12T21:45:03Z

Gyrokinetic Equivalence Catto, Peter

Observation of ion cyclotron range of frequencies mode conversion plasma flow drive on Alcator C-Mod

2019-04-12T21:45:03Z

Observation of ion cyclotron range of frequencies mode conversion plasma flow drive on Alcator C-Mod Lin, Y.; Rice, J.E.; Wukitch, S.J.; Greenwald, M.J.; Hubbard, A.E.; Cushman, A.; Lin, L.; Marmar, M.S.; Porkolab, M.; Reinke, M.L.; Tsujii, N.; Wright, J.C.

MDSplus Objects – Python Implementation

2019-04-12T21:45:03Z

MDSplus Objects – Python Implementation Fredian, T.; Stillerman, J.; Manduchi, G.

Observation of reversed shear Alfvén eigenmodes during sawteeth in Alcator C-Mod

2019-04-10T13:15:55Z

Observation of reversed shear Alfvén eigenmodes during sawteeth in Alcator C-Mod Edlund, E.M.; Porkolab, M.; Kramer, G.J.; Lin, L.; Lin, Y.; Wukitch, S.J.

Role of zonal flows in trapped electron mode turbulence through nonlinear gyrokinetic particle and continuum simulation

2019-04-09T18:53:51Z

Role of zonal flows in trapped electron mode turbulence through nonlinear gyrokinetic particle and continuum simulation Ernst, D.; Lang, J.; Nevins, W.; Hoffman, M.; Chen, Y.; Dorland, W.; Parker, S.

The importance of the effects of diffraction and focusing on current deposition of lower hybrid waves

2019-04-10T13:15:55Z

The importance of the effects of diffraction and focusing on current deposition of lower hybrid waves Wright, J.C.; Bonoli, P.T.; Valeo, E.; Phillips, C.K.; Brambilla, M.; Bilato, R.

Phase contrast imaging measurements of reversed shear Alfvén eigenmodes during sawteeth in Alcator C-Mod

2019-04-10T13:15:54Z

Phase contrast imaging measurements of reversed shear Alfvén eigenmodes during sawteeth in Alcator C-Mod Edlund, E.M.; Porkolab, M.; Kramer, G.J.; Lin, L.; Lin, Y.; Wukitch, S.J.

Studies of turbulence and transport in Alcator C-Mod H-Mode plasmas with phase contrast imaging and comparisons with GYRO

2019-04-12T21:45:02Z

Studies of turbulence and transport in Alcator C-Mod H-Mode plasmas with phase contrast imaging and comparisons with GYRO Lin, L.; Porkolab, M.; Edlund, E.M.; Fiore, C.; Greenwald, M.; Lin, Y.; Mikkelsen, D.; Rost, J.C.; Wukitch, S.J.

Waveguide Splitter For Lower Hybrid Current Drive

2019-04-12T21:45:03Z

Waveguide Splitter For Lower Hybrid Current Drive Koert, P.; Gibbon, P.; Vieira, R.; Terry, D.; Leccacorvi, R.; Doody, J.; Beck, W.

Edge Radial Electric Field Structure and its Connection to H-Mode Confinement in Alcator C-Mod

2019-04-09T18:49:14Z

Edge Radial Electric Field Structure and its Connection to H-Mode Confinement in Alcator C-Mod Dermott, R.M.; Lipschultz, B.; Hughes, J.W.; Catto, P.J.; Hubbard, A.E.; Hutchinson, I.H.; Greenwald, M.; Bombard, B.; Marr, K.; Reinke, M.L.; Rice, J.E.; Whyte, D.G.

Bending-Strain Test Results of ITER Nb3Sn Wires and Preliminary Model Analysis

2019-04-12T21:45:01Z

Bending-Strain Test Results of ITER Nb3Sn Wires and Preliminary Model Analysis Takayasu, Makoto; Chiesa, Luisa; Schultz, Joel; Minervini, Joseph

Studies of turbulence and transportation in Alcator C-Mod ohmic plasmas with phase contrast imaging and comparisons with gyrokinetic simulations

2019-04-12T21:45:02Z

Studies of turbulence and transportation in Alcator C-Mod ohmic plasmas with phase contrast imaging and comparisons with gyrokinetic simulations Lin, L.; Porkolab, M.; Edlund, E.M.; Greenwald, M.; Rost, J.C.; Tsujii, N.; Candy, J.; Waltz, R.E.; Mikkelsen, D.

Hydrogenic retention with high-Z plasma facing surfaces in Alcator C-Mod

2019-04-12T21:45:02Z

Hydrogenic retention with high-Z plasma facing surfaces in Alcator C-Mod Lipschultz, B.; Whyte, D.G.; Irby, J.; Bombard, B.

State Reconstruction and Noise Reduction by Kalman Filter in the Vertical Position Control on Alcator C-Mod

2019-04-12T21:45:02Z

State Reconstruction and Noise Reduction by Kalman Filter in the Vertical Position Control on Alcator C-Mod Ferrara, M.; Hutchinson, I.H.; Wolfe, S.M.

Quasilinear theory of electron transport by radio frequency waves and non-axisymmetric perturbations in toroidal plasmas

2019-04-10T13:15:44Z

Quasilinear theory of electron transport by radio frequency waves and non-axisymmetric perturbations in toroidal plasmas Kominis, Y.; Hizanidis, K.; Ram, A.K.

Zonal flow in a tokamak pedestal

2019-04-10T13:15:44Z

Zonal flow in a tokamak pedestal Kagan, Grigory; Catto, Peter

Cooling topologies for superconducting power systems: I. Short distance electric distribution

2019-04-10T13:15:44Z

Cooling topologies for superconducting power systems: I. Short distance electric distribution Minervini, Joseph

Electron Bernstein Wave Heating and Current Drive in Axisymmetric Toroidal Plasmas

2019-04-09T18:25:20Z

Electron Bernstein Wave Heating and Current Drive in Axisymmetric Toroidal Plasmas Decker, J.; Ram, A.K.; Peysson, Y.; Coda, S.; Curchod, L.; Pochelon, A.

Nonlinear Theory of Cyclotron Resonant Wave-Particle Interactions: Analytical results beyond the Quasilinear Approximation

2019-04-10T13:15:44Z

Nonlinear Theory of Cyclotron Resonant Wave-Particle Interactions: Analytical results beyond the Quasilinear Approximation Kominis, Y.; Hizanidis, K.; Ram, A.K.

Cooling topologies for superconducting power systems: II. Long-distance electric transmission

2019-04-12T21:44:55Z

Cooling topologies for superconducting power systems: II. Long-distance electric transmission Minervini, Joseph

Quasilinear Theory for Momentum and Spatial Diffusion due to Radio Frequency Waves in Non-Axisymmetric Toroidal Plasmas

2019-04-12T21:44:55Z

Quasilinear Theory for Momentum and Spatial Diffusion due to Radio Frequency Waves in Non-Axisymmetric Toroidal Plasmas Kominis, Y.; Hizanidis, K.; Ram, A.K.

Wall-Actuated Scanning Probe(WASP) For High-Field Side Plasma Measurements On Alcator C-Mod

2019-04-12T21:44:55Z

Wall-Actuated Scanning Probe(WASP) For High-Field Side Plasma Measurements On Alcator C-Mod Bombard, Brian

ICRF Specific Impurity Sources and Plasma Sheaths in Alcator C-Mod

2019-04-09T18:21:57Z

ICRF Specific Impurity Sources and Plasma Sheaths in Alcator C-Mod Wukitch, S.J.; Bombard, B.; Lin, Y.; Lipschultz, B.; Marmar, E.; Reinke, M.L.; Whyte, D.G.

Ion Cyclotron Antenna Impurity Production and Real Time Matching in Alcator C-Mod

2019-04-10T13:15:44Z

Ion Cyclotron Antenna Impurity Production and Real Time Matching in Alcator C-Mod Wukitch, S.J.; Lin, Y.; Bombard, B.; Lipschultz, B.; Whyte, D.

Parametric Analysis of the Two-Fluid Tearing Instability

2019-04-12T21:44:54Z

Parametric Analysis of the Two-Fluid Tearing Instability Ramos, Jesus

Oblique ion collection in the drift-approximation: how magnetized Mach-probes really work

2019-04-12T21:44:54Z

Oblique ion collection in the drift-approximation: how magnetized Mach-probes really work Hutchinson, I.H.

Observation of Ion Cyclotron Range of Frequencies Mode Conversion Flow Drive in Tokamak Plasmas

2019-04-12T21:44:55Z

Observation of Ion Cyclotron Range of Frequencies Mode Conversion Flow Drive in Tokamak Plasmas Lin, Y.; Rice, J.E.; Wukitch, S.; Greenwald, M.J.; Hubbard, A.E.; Cushman, A.; Lin, L.; Porkolab, M.; Reinke, M.; Tsujii, N.

Relativistic Effects in Electron Cyclotron Resonance Heating and Current Drive

2019-04-10T13:15:43Z

Relativistic Effects in Electron Cyclotron Resonance Heating and Current Drive Ram, Abhay; Decker, Joan

Chaotic Magnetic Fields Due to Asymmetric Current Configurations - Modeling Cross-Field Particle Diffusion in Cosmic Rays

2019-04-10T13:15:43Z

Chaotic Magnetic Fields Due to Asymmetric Current Configurations - Modeling Cross-Field Particle Diffusion in Cosmic Rays Ram, A.K.; Dasgupta, B.

First measurements of the absolute neutron spectrum using the Magnetic Recoil Spectrometer (MRS) at OMEGA

2019-04-10T13:15:43Z

First measurements of the absolute neutron spectrum using the Magnetic Recoil Spectrometer (MRS) at OMEGA Frenje, J.A.; Casey, D.T.; Li, C.K.; Rygg, J.R.; Seguin, F.H.; Petrasso, R.D.; Glebov, Y.; Meyerhofer, D.D.; Sangster, T.C.; Hatchett, S.; Haan, S.; Cerjan, C.; Landen, O.; Moran, M.; Song, P.; Wilson, D.C.; Leeper, R.J.

Diagnosing ablator areal density and areal density modulations in capsule implosions using charged-particle spectrometry at the National Ignition Facility (NIF)

2019-04-12T21:44:54Z

Diagnosing ablator areal density and areal density modulations in capsule implosions using charged-particle spectrometry at the National Ignition Facility (NIF) Frenje, J.A.; Li, C.K.; Rygg, J.R.; Seguin, F.H.; Casey, D.T.; Petrasso, R.D.; Delettrez, J.; Glebov, Y.; Sangster, T.C.; Landen, O.; Hatchett, S.

Real-time Fast Ferrite ICRF Tuning System on the Alcator C-Mod Tokamak

2019-04-12T21:44:54Z

Real-time Fast Ferrite ICRF Tuning System on the Alcator C-Mod Tokamak Lin, Y.; Binus, A.; Wukitch, S.

Relativistic Propagation and Damping of Electron Cyclotron Waves in Toroidal Plasmas

2019-04-12T21:44:54Z

Relativistic Propagation and Damping of Electron Cyclotron Waves in Toroidal Plasmas Ram, Abhay; Decker, Joan

Observations of Counter-Current Toroidal Rotation in Alcator C-Mod LHCD Plasmas

2019-04-12T21:44:54Z

Observations of Counter-Current Toroidal Rotation in Alcator C-Mod LHCD Plasmas Rice, J.E.; Cushman, A.C.; Bonoli, P.T.; Greenwald, M.J.; Hughes, J.W.; Parker, R.R.; Reinke, M.L.; Wallace, G.M.; Fiore, C.L.; Granetz, R.S.; Hubbard, A.E.; Irby, J.H.; Marmar, E.S.; Shiraiwa, S.; Wolfe, S.M.; Wukitch, S.J.; Bitter, M.; Hill, K.; Wilson, J.R.

Low-Power Testing of Losses in Millimeter-Wave Transmission Lines for High-Power Applications

2019-04-10T13:15:42Z

Low-Power Testing of Losses in Millimeter-Wave Transmission Lines for High-Power Applications Han, S.T.; Comfoltey, E.N.; Shapiro, M.A.; Sirigiri, J.R.; Tax, D.S.; Temkin, R.J.; Woskov, P.P.; Rasmussen, D.A.

Cryostat Optimization Through Multiple Stage Thermal Shields

2019-04-10T13:15:43Z

Cryostat Optimization Through Multiple Stage Thermal Shields Miles, C.; Bromberg, L.; Minervini, J.; Michael, P.

An accelerator based fusion-product source for development of Inertial Confinement Fusion nuclear diagnostics

2019-04-10T13:15:43Z

An accelerator based fusion-product source for development of Inertial Confinement Fusion nuclear diagnostics Duffee, S.C.; Frenje, J.A.; Seguin, F.H.; Leiter, R.; Canavan, M.J.; Casey, D.T.; Rygg, J.R.; Li, C.K.; Petrasso, R.D.

Finite-Larmor-Radius Kinetic Theory of a Magnetized Plasmain the Macroscopic Flow Reference Frame

2019-04-12T21:44:53Z

Finite-Larmor-Radius Kinetic Theory of a Magnetized Plasmain the Macroscopic Flow Reference Frame Ramos, J.J.

Magnetic topology effects on Alcator C-Mod scrape-off layer flow

2019-04-10T13:15:42Z

Magnetic topology effects on Alcator C-Mod scrape-off layer flow Simakov, A.N.; Catto, P.J.; Bombard, B.; Glasser, A.H.

Limitations of Gyrokinetics on Transport Time Scales

2019-04-10T13:15:42Z

Limitations of Gyrokinetics on Transport Time Scales Parra, F.I.; Catto, P.

Spontaneous Core Toroidal Rotation in Alcator C-Mod L-mode, H-mode and ITB Plasmas

2019-04-10T13:15:50Z

Spontaneous Core Toroidal Rotation in Alcator C-Mod L-mode, H-mode and ITB Plasmas Rice, J.E.; Cushman, A.C.; Reinke, M.L.; Podpaly, Y.; Greenwald, M.J.; Bombard, B.; Marmar, E.S.

A General Formulation of MHD Stability Including Flow and a Resistive Wall

2019-04-10T13:15:50Z

A General Formulation of MHD Stability Including Flow and a Resistive Wall Guazzotto, L.; Freidberg, J.P.; Betti, R.

Arbitrary poloidal gyroradius effects in tokamak pedestals and transport barriers

2019-04-12T21:44:59Z

Arbitrary poloidal gyroradius effects in tokamak pedestals and transport barriers Kagan, Grigory; Catto, Peter

Electrostatic turbulence in tokamaks on transport time scales

2019-04-12T21:44:53Z

Electrostatic turbulence in tokamaks on transport time scales Catto, P.J.; Simakov, A.N.; Parra, F.I.; Kagan, G.

Proton radiography of dynamic electric and magnetic fields in laser-produced high-energy-density plasmas

2019-04-10T13:15:41Z

Proton radiography of dynamic electric and magnetic fields in laser-produced high-energy-density plasmas Li, C.K.; Seguin, F.H.; Frenje, J.A.; Manuel, M.; Casey, D.; Sinenian, N.; Petrasso, R.D.; Amendt, P.A.; Landen, O.L.; Rygg, J.R.; Town, R.P.; Betti, R.; Delettrez, J.; Knauer, J.P.; Marshall, F.; Meyerhofer, D.D.; Sangster, T.C.; Shvarts, D.; Smalyuk, V.A.; Soures, J.M.; Back, C.A.; Kilkenny, D.; Nikroo, A.

Observations of the collapse of asymmetrically driven convergent shock

2019-04-10T13:15:42Z

Observations of the collapse of asymmetrically driven convergent shock Rygg, J.R.; Frenje, J.A.; Li, C.K.; Seguin, F.H.; Petrasso, R.D.; Marshalli, F.J.; Delettrez, J.A.; Knauer, J.P.; Meyerhofer, D.D.; Stoeckl, C.

Current Lead Optimization for Cryogenic Operation at Intermediate Temperatures

2019-04-10T13:15:50Z

Current Lead Optimization for Cryogenic Operation at Intermediate Temperatures Bromberg, L.; Michael, P.; Minervini, J.

Proton radiography of inertial fusion implosions

2019-04-10T13:15:42Z

Proton radiography of inertial fusion implosions Seguin, F.H.; Li, C.K.; Frenje, J.A.; Manuel, M.J.; Petrasso, R.D.; Betti, R.; Delettrez, J.A.; Gotchev, O.V.; Knauer, J.P.; Meyerhofer, D.D.; Marshall, F.J.; Stoeckl, C.; Theobald, W.

Benchmarking of Alcohol Chemical Kinetic Mechanism for Laminar Flame Speed Calculations

2019-04-12T21:44:59Z

Benchmarking of Alcohol Chemical Kinetic Mechanism for Laminar Flame Speed Calculations Bromberg, L.

Study of direct-drive capsule implosions in inertial confinement fusion with proton radiography

2019-04-12T21:44:53Z

Study of direct-drive capsule implosions in inertial confinement fusion with proton radiography Li, C.K.; Seguin, F.H.; Rygg, J.R.; Frenje, J.A.; Manuel, M.; Petrasso, R.D.; Smalyuk, V.A.; Betti, R.; Delettrez, J.; Knauer, J.P.; Marshall, F.; Meyerhofer, D.D.; Shvarts, D.; Stoeckl, C.; Theobald, W.; Landen, O.L.; Town, R.P.; Amendt, P.A.; Back, C.A.; Kilkenny, J.D.

Microturbulent drift mode suppression as a trigger mechanism for internal transport barriers on Alcator C-Mod

2019-04-12T21:44:52Z

Microturbulent drift mode suppression as a trigger mechanism for internal transport barriers on Alcator C-Mod Zhurovich, K.; Fiore, C.L.; Ernst, D.R.; Bonoli, P.T.; Greenwald, M.J.; Hubbard, A.E.; Hughes, J.W.; Marmar, E.S.; Mikkelsen, D.R.; Phillips, P.; Rice, J.E.

Ion collection by oblique surfaces of an object in a transversely-flowing strongly-magnetized plasma

2019-04-12T21:44:52Z

Ion collection by oblique surfaces of an object in a transversely-flowing strongly-magnetized plasma Hutchinson, I.H.

Monoenergetic Proton Radiography Measurements of Implosion Dynamics in Direct-Drive Inertial Confinement Fusion

2019-04-12T21:44:53Z

Monoenergetic Proton Radiography Measurements of Implosion Dynamics in Direct-Drive Inertial Confinement Fusion Li, C.K.; Seguin, F.H.; Rygg, J.R.; Frenje, J.A.; Manuel, M.; Petrasso, R.D.; Betti, R.; Delettrez, J.; Knauer, J.P.; Marshall, F.; Meyerhofer, D.D.; Shvarts, D.; Smalyuk, V.A.; Stoeckl, C.; Landen, O.L.; Town, R.P.; Back, C.A.; Kilkenny, J.D.

Full wave simulations of lower hybrid waves in toroidal geometry with non-Maxwellian electrons

2019-04-12T21:44:52Z

Full wave simulations of lower hybrid waves in toroidal geometry with non-Maxwellian electrons Wright, J.C.; Valeo, E.J.; Phillips, C.K.; Bonoli, P.T.; Brambilla, M.

Effective Octane and Efficiency Advantages of Direct Injection Alcohol Engines

2019-04-12T21:44:52Z

Effective Octane and Efficiency Advantages of Direct Injection Alcohol Engines Bromberg, L.; Cohn, D.R.

Effects of energy loss on interaction dynamics of energetic electrons with plasmas

2019-04-12T21:44:52Z

Effects of energy loss on interaction dynamics of energetic electrons with plasmas Li, C.K.; Petrasso, R.D.

Fully self-consistent ion-drag force calculations for dust in collisional plasmas with external electric field

2019-04-11T09:47:02Z

Fully self-consistent ion-drag force calculations for dust in collisional plasmas with external electric field Patacchini, L.; Hutchinson, I.H.

MDSplus Extensions for Long Pulse Experiments

2019-04-10T13:15:41Z

MDSplus Extensions for Long Pulse Experiments Fredian, T.; Stillerman, J.; Manduchi, G.

Critical gradients and plasma flows in the edge plasma of Alcator C-Mod

2019-04-10T13:15:41Z

Critical gradients and plasma flows in the edge plasma of Alcator C-Mod Bombard, B.; Hughes, J.W.; Smick, N.; Graf, A.; Marr, K.; Dermott, R.; Reinke, M.; Greenwald, M.; Lipschultz, B.; Terry, J.L.; Whyte, D.G.; Zweben, S.J.

Calculation of Radiation from a Helically Cut Waveguide for a Gyrotron Mode Converter in the Quasi-Optical Approximation

2019-04-12T21:44:51Z

Calculation of Radiation from a Helically Cut Waveguide for a Gyrotron Mode Converter in the Quasi-Optical Approximation Choi, E.; Shapiro, M.; Sirigiri, J.; Temkin, R.

A study of multiscale density fluctuation measurements

2019-04-12T21:44:51Z

A study of multiscale density fluctuation measurements Basse, N.P.

Fast Electron Driven Modes in the Current Rise in Alcator C-Mod

2019-04-12T21:44:52Z

Fast Electron Driven Modes in the Current Rise in Alcator C-Mod Snipes, J.A.; Parker, R.R.; Schmidt, A.E.; Wallace, G.; Phillips, P.E.

Observation of Large Arrays of Plasma Filaments in Air Breakdown by 1.5 MW, 110 GHz Gyrotron Pulses

2019-04-11T09:47:01Z

Observation of Large Arrays of Plasma Filaments in Air Breakdown by 1.5 MW, 110 GHz Gyrotron Pulses Hidaka, Yoshiteru; Choi, E.M.; Mastovsky, I.; Shapiro, M.; Sirigiri, J.; Temkin, R.

Spontaneous rotation and momentum transport in tokamak plasmas

2019-04-10T13:15:54Z

Spontaneous rotation and momentum transport in tokamak plasmas Rice, J.E.

Notch Filter Options for ITER Stray Gyrotron Radiation

2019-04-10T13:15:54Z

Notch Filter Options for ITER Stray Gyrotron Radiation Woskov, Paul

A Family of Analytic Equilibrium Solutions for the Grad-Shafranov Equation

2019-04-10T13:15:54Z

A Family of Analytic Equilibrium Solutions for the Grad-Shafranov Equation Guazzotto, Luca; Freidberg, Jeffrey

Experimental Observation of the Effect of Aftercavity Interaction in a Depressed Collector Gyrotron Oscillator

2019-04-12T21:44:50Z

Experimental Observation of the Effect of Aftercavity Interaction in a Depressed Collector Gyrotron Oscillator Choi, E.; Shapiro, M.; Sirigiri, J.; Temkin, R.

Mirror Langmuir probe: A technique for real-time measurement of magnetized plasma conditions using a single Langmuir electrode

2019-04-12T21:45:01Z

Mirror Langmuir probe: A technique for real-time measurement of magnetized plasma conditions using a single Langmuir electrode Bombard, B.; Lyons, L.

Time-dependent nuclear measurements of mix in inertial confinement fusion

2019-04-10T13:15:53Z

Time-dependent nuclear measurements of mix in inertial confinement fusion Rygg, J.R.; Frenje, J.A.; Li, C.K.; Seguin, F.H.; Petrasso, R.D.; Glebov, V.; Meyerhofer, D.D.; Sangster, T.C.; Stoeckl, C.

Observation of Megagauss Field Topology Changes due to Magnetic Reconnection in Laser- Produced Plasmas

2019-04-10T13:15:53Z

Observation of Megagauss Field Topology Changes due to Magnetic Reconnection in Laser- Produced Plasmas Li, C.K.; Seguin, F.H.; Town, R.P.; Petrasso, R.D.; Frenje, J.A.; Knauer, J.P.; Landen, O.L.; Rygg, J.R.; Smalyuk, V.A.

Observation of the Decay Dynamics and Instabilities of Megagauss Field Structures in Laser-Produced Plasmas

2019-04-12T21:45:00Z

Observation of the Decay Dynamics and Instabilities of Megagauss Field Structures in Laser-Produced Plasmas Li, C.K.; Seguin, F.H.; Frenje, J.A.; Rygg, J.R.; Petrasso, R.D.; Town, R.P.; Amendt, P.A.; Hatchett, S.P.; Landen, O.L.; Mackinnon, A.J.; Patel, P.K.; Tabak, M.; Knauer, J.P.; Sangster, T.C.; Smalyuk, V.A.

Equilibrium beta limits in a dipole configuration

2019-04-10T13:15:52Z

Equilibrium beta limits in a dipole configuration Guazzotto, L.; Freidberg, J.P.; Kesner, J.

H-mode pedestal and threshold studies over an expanded operating space on Alcator C-Mod

2019-04-10T13:15:53Z

H-mode pedestal and threshold studies over an expanded operating space on Alcator C-Mod Hubbard, Amanda; Hughes, Jerry; Bespamyatnov, Igor; Biewer, Theodore; Cziegler, Istvan; Bombard, Brian; Lin, Yijun; Dermott, Rachel; Rice, John; Rowan, William; Snipes, Joseph; Terry, James; Wolfe, Steve; Wukitch, Steven

Quasilinear theory of interchange modes in a closed field line configuration

2019-04-12T21:45:00Z

Quasilinear theory of interchange modes in a closed field line configuration Kouznetsov, A.; Freidberg, J.P.; Kesner, J.

Theoretical prediction of beta and confinement time in a hardcore Z-pinch

2019-04-12T21:45:00Z

Theoretical prediction of beta and confinement time in a hardcore Z-pinch Kouznetsov, Alexey; Freidberg, Jeffrey; Kesner, Jay

Electron collection by a negatively charged sphere in a collisionless magnetoplasma

2019-04-12T21:45:00Z

Electron collection by a negatively charged sphere in a collisionless magnetoplasma Patacchini, L.; Hutchinson, I.H.; Lapenta, G.

Effect of Compression Ratio and Manifold Pressure on Ethanol Utilizationin Gasoline/Ethanol Engines

2019-04-12T21:45:00Z

Effect of Compression Ratio and Manifold Pressure on Ethanol Utilizationin Gasoline/Ethanol Engines Bromberg, L.; Cohn, D.R.

Alcator C-Mod Ion Cyclotron Antenna Performance

2019-04-10T13:15:50Z

Alcator C-Mod Ion Cyclotron Antenna Performance Wukitch, S.J.; Graves, T.; Lin, Y.; Lipschultz, B.; Parisot, A.; Reinke, M.; Bonoli, P.T.; Porkolab, M.; Hutchinson, I.H.; Marmar, E.

The effect of sheared axial flow on the interchange mode in a hard-core Z-pinch

2019-04-10T13:15:50Z

The effect of sheared axial flow on the interchange mode in a hard-core Z-pinch Kouznetsov, A.; Freidberg, J.P.; Kesner, J.

Influence of boronization on operation with high-Z plasma facing components in Alcator C-Mod

2019-04-10T13:15:51Z

Influence of boronization on operation with high-Z plasma facing components in Alcator C-Mod Lipschultz, B.; Lin, Y.; Marmar, E.S.; Whyte, D.G.; Wukitch, S.; Hutchinson, I.H.; Irby, J.; Bombard, B.; Reinke, M.L.; Terry, J.L.; Wright, G.

Plasma-surface interaction, scrape-off layer and divertor physics: Implications for ITER

2019-04-10T13:15:52Z

Plasma-surface interaction, scrape-off layer and divertor physics: Implications for ITER Lipschultz, B.; Bonnin, X.; Counsell, G.; Kallenbach, A.; Kukushkin, A.; Krieger, K.; Leonard, A.; Loarte, A.; Neu, R.; Pitts, R.A.; Rognlien, T.; Roth, J.; Skinner, C.; Terry, J.L.; Tsitrone, E.; Whyte, D.; Zweben, S.; Asakura, N.; Coster, D.; Doerner, R.; Dux, R.; Federici, G.; Fenstermacher, M.; Fundamenski, W.; Ghendrih, P.; Herrmann, A.; Hu, J.; Krasheninnikov, S.; Kirnev, G.; Kreter, A.; Kurnaev, V.; Bombard, B.; Lisgo, S.; Nakano, T.; Ohno, N.; Pacher, H.D.; Paley, J.; Pan, Y.; Pautasso, G.; Philipps, V.; Rohde, V.; Rudakov, D.; Stangeby, P.; Takamura, S.; Tanabe, T.; Yang, Y.; Zhu, S.

Hydrogenic Fuel Recovery and Retention with Metallic Plasma-Facing Walls in the Alcator C-Mod Tokamak

2019-04-10T13:15:50Z

Hydrogenic Fuel Recovery and Retention with Metallic Plasma-Facing Walls in the Alcator C-Mod Tokamak Whyte, D.G.; Lipschultz, B.; Irby, J.; Granetz, R.; Bombard, B.; Terry, J.; Wright, G.M.

Operation of Alcator C-Mod with High-Z Plasma Facing Components With and Without Boronization

2019-04-10T13:15:49Z

Operation of Alcator C-Mod with High-Z Plasma Facing Components With and Without Boronization Marmar, E.; Lin, Y.; Lipschultz, B.; Whyte, D.; Bonoli, P.; Fiore, C.; Greenwald, M.; Hutchinson, I.; Irby, J.; Reinke, M.; Rice, J.; Scott, S.; Terry, J.; Wolfe, S.; Wukitch, S.

Inter-Machine Comparison of Intrinsic Toroidal Rotation

2019-04-10T13:15:49Z

Inter-Machine Comparison of Intrinsic Toroidal Rotation Rice, J.E.; Cushman, A.; Grassie, J.S.; Eriksson, L.; Sakamoto, Y.; Scarabosio, A.; Bortolon, A.; Burrell, K.H.; Bonizec, C.; Greenwald, M.J.; Groebner, R.J.; Hoang, G.T.; Koide, Y.; Marmar, E.S.; Pochelon, A.; Podpaly, Y.

Experimental Studies and Analysis of Alfvén Eigenmodes in Alcator C-Mod

2019-04-12T21:44:59Z

Experimental Studies and Analysis of Alfvén Eigenmodes in Alcator C-Mod Porkolab, M.; Edlund, E.; Lin, L.; Parker, R.; Rost, C.; Sears, J.; Snipes, J.; Wukitch, S.J.; Breizman, B.; Gorelenkov, N.; Kramer, G.J.; Fasoli, A.; Smith, H.

Gas Jet Disruption Mitigation Studies on Alcator C-Mod and DIII-D

2019-04-10T13:15:48Z

Gas Jet Disruption Mitigation Studies on Alcator C-Mod and DIII-D Hollmann, E.M.; Whyte, D.G.; Izzo, V.A.; Antar, G.Y.; Bader, A.; Bakhtiari, M.; Biewer, T.; Boedo, J.A.; Evans, T.E.; Hutchinson, I.H.; Jernigan, T.C.; Gray, D.S.; Groth, M.; Humphreys, D.A.; Lasnier, C.J.; Moyer, R.A.; Parks, P.B.; Reinke, M.L.; Rudakov, D.L.; Strait, E.J.; Terry, J.L.; Wesley, J.; West, W.P.; Wurden, G.; Yu, J.

Plasma-surface interaction, scrape-off layer and divertor physics:Implications for ITER

2019-04-10T13:15:49Z

Plasma-surface interaction, scrape-off layer and divertor physics:Implications for ITER Lipschultz, B.; Bonnin, X.; Kukushkin, A.; Leonard, A.; Roth, J.; Tsitrone, E.; Whyte, D.; Asakura, N.; Coster, D.; Counsell, G.; Doerner, R.; Dux, R.; Federici, G.; Fenstermacher, M.; Fundamenski, W.; Ghendrih, P.; Herrmann, A.; Hu, J.; Kallenbach, A.; Krasheninnikov, S.; Krieger, K.; Kirnev, G.; Kreter, A.; Kurnaev, V.; Bombard, B.; Lisgo, S.; Loarte, A.; Nakano, T.; Neu, R.; Ohno, N.; Pacher, H.; Paley, J.; Pan, Y.; Pautasso, G.; Philipps, V.; Pitts, R.; Riccardo, V.; Rohde, V.; Rudakov, D.; Stangeby, P.; Takamura, S.; Tanabe, T.; Yang, Y.; Zhu, S.

Edge profile stiffness and insensitivity of the density pedestal to neutral fueling in Alcator C-Mod edgetransport barriers

2019-04-10T13:15:48Z

Edge profile stiffness and insensitivity of the density pedestal to neutral fueling in Alcator C-Mod edgetransport barriers Hughes, J.W.; Bombard, B.; Terry, J.; Hubbard, A.; Lipschultz, B.

MHD Simulations for Studies of Disruption Mitigation by High Pressure Noble Gas Injection

2019-04-10T13:15:49Z

MHD Simulations for Studies of Disruption Mitigation by High Pressure Noble Gas Injection Izzo, V.A.; Granetz, R.S.; Whyte, D.G.; Bakhtiari, M.

Identification of TEM Turbulence through Direct Comparison of Nonlinear Gyrokinetic Simulations with Phase Contrast Imaging Density Fluctuation Measurements

2019-04-12T21:44:59Z

Identification of TEM Turbulence through Direct Comparison of Nonlinear Gyrokinetic Simulations with Phase Contrast Imaging Density Fluctuation Measurements Ernst, D.R.; Basse, N.; Dorland, W.; Fiore, C.L.; Lin, L.; Long, A.; Porkolab, M.; Zeller, K.; Zhurovich, K.

Collisional bulk ion transport and poloidal rotation driven by neutral beam injection

2019-04-10T13:15:46Z

Collisional bulk ion transport and poloidal rotation driven by neutral beam injection Newton, Sarah; Helander, Per; Catto, Peter

Benchmarking of Lower Hybrid Current Drive Codes with Applications to ITER-Relevant Regimes

2019-04-10T13:15:48Z

Benchmarking of Lower Hybrid Current Drive Codes with Applications to ITER-Relevant Regimes Bonoli, P.T.; Harvey, R.W.; Kessel, C.; Imbeaux, F.; Oikawa, T.; Schneider, M.; Barbato, E.; Decker, J.; Giruzzi, G.; Forest, C.B.; Ide, S.; Peysson, Y.; Schmidt, A.E.; Sips, A.C.; Smirnov, A.P.; Wright, J.C.

Spectroscopic measurements of a 5 - 30 kHz, high voltage atmospheric pressure discharge

2019-04-12T21:44:56Z

Spectroscopic measurements of a 5 - 30 kHz, high voltage atmospheric pressure discharge Hadidi, Kamal; Woskov, Paul

Effects of finite poloidal gyroradius, shaping, and collisions on the zonal flow residual

2019-04-12T21:44:58Z

Effects of finite poloidal gyroradius, shaping, and collisions on the zonal flow residual Xiao, Yong; Catto, Peter; Dorland, William

Fluid Theory of Magnetized Plasma Dynamics at Low Collisionality

2019-04-12T21:44:55Z

Fluid Theory of Magnetized Plasma Dynamics at Low Collisionality Ramos, J.J.

Relativistic description of electron Bernstein waves

2019-04-11T00:44:50Z

Relativistic description of electron Bernstein waves Decker, J.; Ram, A.K.

Collisional zonal flow damping for ITG modes

2019-04-11T00:44:50Z

Collisional zonal flow damping for ITG modes Xiao, Yong; Catto, Peter; Molvig, Kim

Inter-Machine Comparison of Intrinsic Toroidal Rotation

2019-04-12T21:43:07Z

Inter-Machine Comparison of Intrinsic Toroidal Rotation Rice, J.E.; Cushman, A.; Grassie, J.S.; Eriksson, L.; Sakamoto, Y.; Scarabosio, A.; Bortolon, A.; Burrell, K.H.; Duval, B.P.; Bonizec, C.; Greenwald, M.J.; Groebner, R.J.; Hoang, G.T.; Koide, Y.; Marmar, E.S.; Pochelon, A.; Podpaly, Y.

Plasma shaping effects on the collisionless residual zonal flow level

2019-04-12T21:43:07Z

Plasma shaping effects on the collisionless residual zonal flow level Xiao, Yong; Catto, Peter

Isothermal tokamak

2019-04-12T21:43:07Z

Isothermal tokamak Catto, Peter; Hazeltine, Richard

Comparison of solid and plasma linear energy deposition for electron preheat and fast ignition scenarios

2019-04-12T21:43:07Z

Comparison of solid and plasma linear energy deposition for electron preheat and fast ignition scenarios Chen, C.D.; Li, C.K.; Petrasso, R.D.

The operational phase space of the edge plasma and its sensitivity to magnetic topology in Alcator C-Mod

2019-04-11T00:44:49Z

The operational phase space of the edge plasma and its sensitivity to magnetic topology in Alcator C-Mod Bombard, B.; Smick, N.; Greenwald, M.; Hughes, J.W.; Lipschultz, B.; Marr, K.; Terry, J.L.

Self-consistent radial electric field in collisional screw-pinches and magnetic dipoles in the absence of fluctuations

2019-04-12T21:43:06Z

Self-consistent radial electric field in collisional screw-pinches and magnetic dipoles in the absence of fluctuations Simakov, Andrei; Catto, Peter

Short wavelength effect on the collisionless neoclassical polarization and residual zonal flow level

2019-04-12T21:43:06Z

Short wavelength effect on the collisionless neoclassical polarization and residual zonal flow level Xiao, Yong; Catto, Peter

Hydrogen Control in Alcator C-Mod Walls and Plasmas

2019-04-12T21:43:06Z

Hydrogen Control in Alcator C-Mod Walls and Plasmas Lin, Y.; Irby, J.; Lipschultz, B.; Marmar, E.; Whyte, D.; Wolfe, S.; Wukitch, S.

Test Plan for: Pre-Operational Testing of MERIT BNL - E951/(n-ToF-11), 15T Pulsed Magnet for Mercury Target Development Neutrino Factory and Muon Collider Collaboration

2019-04-12T21:44:58Z

Test Plan for: Pre-Operational Testing of MERIT BNL - E951/(n-ToF-11), 15T Pulsed Magnet for Mercury Target Development Neutrino Factory and Muon Collider Collaboration Titus, P.H.

Test Results: Pre-Operational Testing of MERIT BNL - E951/(n-ToF-11), 15T Pulsed Magnet for Mercury Target Development Neutrino Factory and Muon Collider Collaboration

2019-04-12T21:44:58Z

Test Results: Pre-Operational Testing of MERIT BNL - E951/(n-ToF-11), 15T Pulsed Magnet for Mercury Target Development Neutrino Factory and Muon Collider Collaboration Titus, P.H.

Direct Injection Ethanol Boosted Gasoline Engines:Biofuel Leveraging For Cost Effective Reduction of Oil Dependence and CO2Emissions

2019-04-10T13:15:48Z

Direct Injection Ethanol Boosted Gasoline Engines:Biofuel Leveraging For Cost Effective Reduction of Oil Dependence and CO2Emissions Cohn, D.R.; Bromberg, L.; Heywood, J.B.

Magnetic Topology Effects on Alcator C-Mod Flows

2019-04-12T21:44:57Z

Magnetic Topology Effects on Alcator C-Mod Flows Catto, Peter

RF-Plasma Edge Interactions and their Impact on ICRF Antenna Performance in Alcator C-Mod

2019-04-10T20:27:58Z

RF-Plasma Edge Interactions and their Impact on ICRF Antenna Performance in Alcator C-Mod Wukitch, S.J.; Lipschultz, B.; Marmar, E.; Lin, Y.; Parisot, A.; Reinke, M.; Rice, J.; Terry, J.

A Comparison of Measured and Calculated Toroidal Alfven Eigenmode Damping Rates in Alcator C-Mod

2019-04-12T21:44:57Z

A Comparison of Measured and Calculated Toroidal Alfven Eigenmode Damping Rates in Alcator C-Mod Snipes, J.A.; Gorelenkov, N.N.; Sears, J.A.

Sawtooth period changes with mode conversion current drive on Alcator C-Mod

2019-04-12T21:44:58Z

Sawtooth period changes with mode conversion current drive on Alcator C-Mod Parisot, A.; Wukitch, S.J.; Bonoli, P.; Greenwald, M.; Hubbard, A.; Lin, Y.; Parker, R.; Porkolab, M.; Ram, A.K.; Wright, J.C.

Measuring E and B fields in Laser-Produced Plasmas with Monoenergetic Proton Radiography

2019-04-10T13:15:47Z

Measuring E and B fields in Laser-Produced Plasmas with Monoenergetic Proton Radiography Li, C.K.; Seguin, F.H.; Frenje, J.A.; Rygg, J.R.; Petrasso, R.D.; Town, R.P.; Amendt, P.A.; Hatchett, S.P.; Landen, O.L.; Mackinnon, A.J.; Patel, P.K.; Smalyuk, V.A.; Sangster, T.C.; Knauer, J.P.

Proton core imaging of the nuclear burn in inertial confinement fusion implosions

2019-04-10T13:15:48Z

Proton core imaging of the nuclear burn in inertial confinement fusion implosions Ciantis, J.L.; Seguin, F.H.; Frenje, J.A.; Berube, V.; Canavan, M.J.; Chen, C.D.; Kurebayashi, S.; Li, C.K.; Rygg, J.R.; Schwartz, B.E.; Petrasso, R.D.; Delettrez, J.A.; Regan, S.P.; Smalyuk, V.A.; Knauer, J.P.; Marshall, F.J.; Meyerhofer, D.D.; Roberts, S.; Sangster, T.C.; Stoeckl, C.; Mikaelian, K.; Park, H.S.; Robey, H.F.

Tests of the hydrodynamic equivalence of direct-drive implosions with difference D[sub 2] and [sup 3]He mixtures

2019-04-10T13:15:48Z

Tests of the hydrodynamic equivalence of direct-drive implosions with difference D[sub 2] and [sup 3]He mixtures Rygg, J.R.; Frenje, J.A.; Li, C.K.; Seguin, F.H.; Petrasso, R.D.; Delettrez, J.A.; Glebov, V.; Goncharov, V.N.; Meyerhofer, D.D.; Regan, S.P.; Sangster, T.C.; Stoeckl, C.

Measured dependence of nuclear burn region size on implosion parameters in inertial confinement fusion experiments

2019-04-12T21:44:57Z

Measured dependence of nuclear burn region size on implosion parameters in inertial confinement fusion experiments Seguin, F.H.; Ciantis, J.L.; Frenje, J.A.; Li, C.K.; Rygg, J.R.; Chen, C.D.; Petrasso, R.D.; Delettrez, J.A.; Regan, S.P.; Smalyuk, V.A.; Glebov, V.; Knauer, J.P.; Marshall, F.J.; Meyerhofer, D.D.; Roberts, S.; Sangster, T.C.; Stoeckl, C.; Mikaelian, K.; Park, H.S.; Robey, H.F.; Tipton, R.E.

A monoenergetic proton backlighter for measuring E and B fields and for radiographing implosions and HED plasmas

2019-04-12T21:44:57Z

A monoenergetic proton backlighter for measuring E and B fields and for radiographing implosions and HED plasmas Li, C.K.; Seguin, F.H.; Frenje, J.A.; Rygg, J.R.; Petrasso, R.D.; Town, R.P.; Amendt, P.A.; Hatchett, S.P.; Landen, O.L.; Mackinnon, A.J.; Patel, P.K.; Smalyuk, V.A.; Knauer, J.P.; Sangster, T.C.; Stoeckl, C.

Onboard Plasmatron Hydrogen Production for Improved Vehicles

2019-04-10T13:15:47Z

Onboard Plasmatron Hydrogen Production for Improved Vehicles Bromberg, L.; Cohn, D.R.; Rabinovich, A.; Alexeev, N.; Samokhin, A.; Hadidi, K.; Palaia, J.; Bel, N.

Energy deposition of MeV electrons in compressed targets of fast-ignition inertial confinement fusion

2019-04-10T13:15:47Z

Energy deposition of MeV electrons in compressed targets of fast-ignition inertial confinement fusion Li, C.K.; Petrasso, R.D.

Heat and momentum transport in arbitrary mean-free path plasma with a Maxwellian lowest order distribution function

2019-04-09T18:25:09Z

Heat and momentum transport in arbitrary mean-free path plasma with a Maxwellian lowest order distribution function Simakov, Andrei; Catto, Peter

Stopping, Straggling, and Blooming of Directed Energetic Electrons in Hydrogenic and Arbitrary-Z Plasmas

2019-04-10T13:15:47Z

Stopping, Straggling, and Blooming of Directed Energetic Electrons in Hydrogenic and Arbitrary-Z Plasmas Li, C.K.; Petrasso, R.D.

Web Based Electronic Logbook and Experiment Run Database Viewer for Alcator C-Mod

2019-04-10T13:15:46Z

Web Based Electronic Logbook and Experiment Run Database Viewer for Alcator C-Mod Fredian, T.W.; Stillerman, J.

Calculations Of Knock Suppression in Highly Turbocharged Gasoline/Ethanol Engines Using Direct Ethanol Injection

2019-04-10T13:15:47Z

Calculations Of Knock Suppression in Highly Turbocharged Gasoline/Ethanol Engines Using Direct Ethanol Injection Bromberg, L.; Cohn, D.R.; Heywood, J.B.

Theoretical and Experimental Contributions of MIT to the FusionScience Center, and Findings of the Electron Transport Task Force

2019-04-12T21:44:57Z

Theoretical and Experimental Contributions of MIT to the FusionScience Center, and Findings of the Electron Transport Task Force Petrasso, R.D.; Li, C.K.; Seguin, F.H.; Chen, C.; Case, D.

Visions for data management and remote collaboration for ITER

2019-04-12T21:44:56Z

Visions for data management and remote collaboration for ITER Greenwald, M.; Schissel, D.; Burruss, J.R.; Fredian, T.; Lister, J.; Stillerman, J.

Startup characteristics of plasmatron gasoline reformers

2019-04-12T21:44:56Z

Startup characteristics of plasmatron gasoline reformers Bromberg, L.

Effects of hot electrons on the stability of a dipolar plasma

2019-04-12T21:44:57Z

Effects of hot electrons on the stability of a dipolar plasma Krasheninnikova, Natalia; Catto, Peter

Advances in measurement and modeling of the high-confinement-mode pedestal on the Alcator C-Mod tokamak

2019-04-10T13:15:46Z

Advances in measurement and modeling of the high-confinement-mode pedestal on the Alcator C-Mod tokamak Hughes, J.W.; Bombard, B.; Mossessian, D.A.; Hubbard, A.E.; Terry, J.; Biewer, T.

C-MOD REVIEW: Diagnostic Systems On Alcator C-MOD

2019-04-10T13:15:46Z

C-MOD REVIEW: Diagnostic Systems On Alcator C-MOD Basse, N.P.; Dominguez, A.; Edlund, E.M.; Fiore, C.L.; Granetz, R.S.; Hubbard, A.E.; Hughes, J.W.; Hutchinson, I.H.; Irby, J.H.; Labombard, B.; Lin, L.; Lin, Y.; Lipschultz, B.; Liptac, J.E.; Marmar, E.S.; Mossessian, D.A.; Parker, R.R.; Porkolab, M.; Rice, J.E.; Snipes, J.A.; Tang, V.; Terry, J.L.

C-MOD REVIEW: Core Atomic Physics Studies in Alcator C-Mod

2019-04-12T21:43:05Z

C-MOD REVIEW: Core Atomic Physics Studies in Alcator C-Mod Rice, J.E.; Terry, J.L.; Fourniery, K.B.; Marmar, E.S.

Operation of Alcator C-Mod with high-Z plasma facing components and implications

2019-04-12T21:44:56Z

Operation of Alcator C-Mod with high-Z plasma facing components and implications Lipschultz, B.; Lin, Y.; Reinke, M.L.; Whyte, D.; Hubbard, A.; Hutchinson, I.H.; Irby, J.; Bombard, B.; Marmar, E.S.; Marr, K.; Terry, J.L.; Wolfe, S.M.

C-MOD REVIEW: Alcator C-Mod Design and Engineering

2019-04-12T21:44:56Z

C-MOD REVIEW: Alcator C-Mod Design and Engineering Irby, J.H.; Gwinn, D.; Beck, W.; Vieira, R.

Divertor physics research on Alcator C-Mod

2019-04-11T00:44:49Z

Divertor physics research on Alcator C-Mod Lipschultz, B.; Bombard, B.; Terry, J.L.; Boswell, C.; Hutchinson, I.H.

Neutrals studies on Alcator C-Mod

2019-04-12T21:43:05Z

Neutrals studies on Alcator C-Mod Lipschultz, B.; Bombard, B.; Lisgo, S.; Terry, J.L.

C-MOD REVIEW: XI. Energetic Particle Physics Studies on Alcator C-Mod

2019-04-12T21:43:05Z

C-MOD REVIEW: XI. Energetic Particle Physics Studies on Alcator C-Mod Snipes, J.A.; Basse, N.; Bonoli, P.; Boswell, C.; Edlund, E.; Fasoli, A.; Granetz, R.S.; Lin, L.; Lin, Y.; Parker, R.; Porkolab, M.; Sears, J.; Tang, V.; Wukitch, S.

Wave-Particle Studies in the Ion Cyclotron and Lower Hybrid Range of Frequencies in Alcator C-Mod

2019-04-12T21:43:05Z

Wave-Particle Studies in the Ion Cyclotron and Lower Hybrid Range of Frequencies in Alcator C-Mod Bonoli, P.T.; Parker, R.; Wukitch, S.J.; Lin, Y.; Porkolab, M.; Wright, J.C.; Edlund, E.; Graves, T.; Lin, L.; Liptac, J.; Parisot, A.; Schmitt, A.E.; Tang, V.; Beck, W.; Childs, R.; Grimes, M.; Gwinn, D.; Johnson, D.; Irby, J.; Kanojia, A.; Koert, P.; Marazita, S.; Marmar, E.; Terry, D.; Vieira, R.; Wallace, G.; Zaks, J.; Bernabei, S.; Brunkhorse, C.; Ellis, R.; Fredd, E.; Greenough, N.; Hosea, J.; Kung, C.C.; Loesser, G.D.; Rushinski, J.; Schilling, G.; Phillips, C.K.; Wilson, J.R.; Harvey, R.W.; Fiore, C.L.; Granetz, R.; Greenwald, M.; Hubbard, A.E.; Hutchinson, I.H.; Labombard, B.; Lipschultz, B.; Rice, J.; Snipes, J.A.; Terry, J.; Wolfe, S.M.

C-MOD REVIEW: Internal Transport Barriers in Alcator C-Mod

2019-04-11T00:44:48Z

C-MOD REVIEW: Internal Transport Barriers in Alcator C-Mod Fiore, C.L.; Ernst, D.R.; Rice, J.E.; Zhurovich, K.; Basse, N.; Bonoli, P.T.; Greenwald, M.J.; Marmar, E.S.; Wukitch, S.J.

C-MOD REVIEW: Impurity Transport in Alcator C-Mod Plasmas

2019-04-11T00:44:49Z

C-MOD REVIEW: Impurity Transport in Alcator C-Mod Plasmas Rice, J.E.; Terry, J.L.; Marmar, E.S.; Granetz, R.S.; Greenwald, M.J.; Hubbard, A.E.; Irby, J.H.; Pedersen, T.; Wolfe, S.M.

C-MOD REVIEW: H-mode pedestal and L-H transition studies on Alcator C-Mod

2019-04-15T00:27:25Z

C-MOD REVIEW: H-mode pedestal and L-H transition studies on Alcator C-Mod Hughes, J.W.; Hubbard, A.E.; Mossessian, D.A.; Bombard, B.; Biewer, T.M.; Granetz, R.S.; Greenwald, M.; Hutchinson, I.H.; Irby, J.H.; Lin, Y.; Marmar, E.S.; Porkolab, M.; Rice, J.E.; Snipes, J.A.; Terry, J.L.; Wolfe, S.; Zhurovich, K.

The Scrape-Off-Layer in Alcator C-Mod â€“Transport, Turbulence, and Flows

2019-04-12T21:43:04Z

The Scrape-Off-Layer in Alcator C-Mod â€“Transport, Turbulence, and Flows Terry, J.L.; Bombard, B.; Lipschultz, B.; Greenwald, M.J.; Rice, J.E.; Zweben, S.J.

C-MOD REVIEW: Confinement and Transport Research in Alcator C-Mod

2019-04-11T00:44:48Z

C-MOD REVIEW: Confinement and Transport Research in Alcator C-Mod Greenwald, M.; Basse, N.; Bonoli, P.; Bravenec, R.; Edlund, E.; Ernst, D.; Fiore, C.; Granetz, R.; Hubbard, A.; Hughes, J.; Hutchinson, I.; Irby, J.; Bombard, B.; Lin, L.; Lin, Y.; Lipschultz, B.; Marmar, E.; Mikkelsen, D.; Mossessian, D.; Phillips, P.; Porkolab, M.; Rice, J.

Comparison of particle transport in the Scrapeoff Layer plasmas of Alcator C-Mod and DIII-D

2019-04-12T21:43:04Z

Comparison of particle transport in the Scrapeoff Layer plasmas of Alcator C-Mod and DIII-D Lipschultz, B.; Whyte, D.G.; Bombard, B.

The Alcator C-Mod Program

2019-04-10T20:29:02Z

The Alcator C-Mod Program Marmar, E.S.

C-MOD REVIEW: Spontaneous Toroidal Rotation in Alcator C-Mod Plasmas with No Momentum Input

2019-04-12T21:43:04Z

C-MOD REVIEW: Spontaneous Toroidal Rotation in Alcator C-Mod Plasmas with No Momentum Input Rice, J.E.; Marmar, E.S.; Bonoli, P.T.; Granetz, R.S.; Greenwald, M.J.; Hubbard, A.E.; Hughes, J.W.; Hutchinson, I.H.; Irby, J.H.; Bombard, B.; Lee, W.D.; Lin, Y.; Mossessian, D.; Snipes, J.A.; Wolfe, S.M.; Wukitch, S.J.

Comparisons of small ELM H-Mode regimes on the Alcator C-Mod and JFT-2M tokamaks

2019-04-11T00:44:48Z

Comparisons of small ELM H-Mode regimes on the Alcator C-Mod and JFT-2M tokamaks Hubbard, A.E.; Kamiya, K.; Oyama, N.; Basse, N.; Biewer, T.; Edlund, E.; Hughes, J.W.; Lin, L.; Porkolab, M.; Rowan, W.; Snipes, J.; Terry, J.; Wolfe, S.M.

A New, Explicitly Collisional Contribution to the Gyroviscosity and the Radial Electric Field in a Collisional Tokamak

2019-04-09T18:27:50Z

A New, Explicitly Collisional Contribution to the Gyroviscosity and the Radial Electric Field in a Collisional Tokamak Catto, Peter; Simakov, Andrei

The Magnitude of Plasma Flux to the Main-wall in the DIII-D Tokamak

2019-04-11T00:44:47Z

The Magnitude of Plasma Flux to the Main-wall in the DIII-D Tokamak Whyte, D.G.; Lipschultz, B.; Stangeby, P.C.; Boedo, J.; Rudakov, D.L.; Watkins, J.G.; West, W.P.

Physics and Technology of the Feasibility of Plasma Sails

2019-04-15T00:27:29Z

Physics and Technology of the Feasibility of Plasma Sails Cattell, C.; Catto, P.; Funsten, H.; Garnier, D.; Hershkowitz, N.; Myers, R.; Petschek, H.; Winske, D.

The Coaxial Multipactor Experiment (CMX): A facility for investigating multipactor discharges

2019-04-12T21:43:04Z

The Coaxial Multipactor Experiment (CMX): A facility for investigating multipactor discharges Graves, T.P.; Bombard, B.; Wukitch, S.J.; Hutchinson, I.H.

Plasmatron Fuel Reformer Development and Internal Combustion Engine Vehicle Applications

2019-04-09T19:27:25Z

Plasmatron Fuel Reformer Development and Internal Combustion Engine Vehicle Applications Bromberg, L.; Cohn, D.R.; Hadidi, K.; Heywood, J.B.; Rabinovich, A.

Evidence for electromagnetic fluid drift turbulence controlling the edge plasma state in the Alcator C-Mod tokamak

2019-04-10T17:53:38Z

Evidence for electromagnetic fluid drift turbulence controlling the edge plasma state in the Alcator C-Mod tokamak Bombard, B.; Hughes, J.W.; Mossessian, D.; Greenwald, M.; Lipschultz, B.; Terry, J.L.

Relativistic Modifications to Electron Bernstein Waves

2019-04-09T17:39:18Z

Relativistic Modifications to Electron Bernstein Waves Ram, Abhay; Decker, Joan

On Electron Bernstein Waves in Spherical Tori

2019-04-10T17:53:27Z

On Electron Bernstein Waves in Spherical Tori Ram, Abhay; Decker, Joan; Peysson, Yves

In-Cylinder Laminar Flame Propagation Speed: Effect of Hydrogen And Hydrogen Rich Gas Addition

2019-04-15T00:27:29Z

In-Cylinder Laminar Flame Propagation Speed: Effect of Hydrogen And Hydrogen Rich Gas Addition Bromberg, L.

Overview of High Power CTS Experiments in Magnetically Confined Plasmas

2019-04-15T00:27:29Z

Overview of High Power CTS Experiments in Magnetically Confined Plasmas

Vlasov simulations of trapping and inhomogeneity in Raman scattering

2019-04-15T00:27:28Z

Vlasov simulations of trapping and inhomogeneity in Raman scattering Strozzi, D.J.; Shoucri, M.M.; Bers, A.; Williams, E.A.; Langdon, A.B.

Current Drive by Electron Bernstein Waves in Spherical Tori

2019-04-15T00:27:29Z

Current Drive by Electron Bernstein Waves in Spherical Tori Ram, A.K.; Decker, J.; Taylor, G.; Efthimion, P.C.; Davies, C.N.; Cairns, R.A.

CFD modeling of Plasmatron Methane Reformer

2019-04-15T00:27:28Z

CFD modeling of Plasmatron Methane Reformer Bromberg, L.

Experimental Investigation of Plasma Assisted Reforming of Propane

2019-04-15T00:27:28Z

Experimental Investigation of Plasma Assisted Reforming of Propane Bromberg, L.; Hadidi, K.; Cohn, D.R.

General Expression of the Gyroviscous Force

2019-04-10T17:53:50Z

General Expression of the Gyroviscous Force Ramos, J.J.

Plasma Assisted Reforming of Methane: Two Stage Perfectly Stirred Reactor (PSR) Simulation

2019-04-10T17:53:50Z

Plasma Assisted Reforming of Methane: Two Stage Perfectly Stirred Reactor (PSR) Simulation Bromberg, L.; Alexeev, N.

Experimental Investigation of Plasma Assisted Reforming of Methane I: Steady State Operation

2019-04-15T00:27:27Z

Experimental Investigation of Plasma Assisted Reforming of Methane I: Steady State Operation Bromberg, L.; Hadidi, K.; Cohn, D.R.

Plasma Assisted Reforming of Methane II: Partially Stirred Reactor (PaSR) Simulation

2019-04-15T00:27:28Z

Plasma Assisted Reforming of Methane II: Partially Stirred Reactor (PaSR) Simulation Bromberg, L.

Experimental Investigation of Plasma Assisted Reforming of Methane II: Start-up

2019-04-15T00:27:28Z

Experimental Investigation of Plasma Assisted Reforming of Methane II: Start-up Bromberg, L.; Hadidi, K.; Cohn, D.R.

Corrugated Waveguide and Directional Coupler for CW 250 GHz Gyrotron DNP Experiments

2019-04-10T17:53:49Z

Corrugated Waveguide and Directional Coupler for CW 250 GHz Gyrotron DNP Experiments Woskov, P.P.; Bajaj, V.S.; Hornstein, M.K.; Temkin, R.J.; Griffin, R.J.

Observation and Modeling of Ion Cyclotron Range of Frequencies Waves in the Mode Conversion Region of Alcator C-Mod

2019-04-10T17:53:50Z

Observation and Modeling of Ion Cyclotron Range of Frequencies Waves in the Mode Conversion Region of Alcator C-Mod Lin, Y.; Wukitch, S.; Parisot, A.; Wright, J.C.; Basse, N.; Bonoli, P.; Edlund, E.; Lin, L.; Porkolab, M.; Schilling, G.; Phillips, P.

Density fluctuations on mm and Mpc scales

2019-04-15T00:27:27Z

Density fluctuations on mm and Mpc scales Basse, N.P.

Evidence for electromagnetic fluid drift turbulence controlling the edge plasma state in the Alcator C-Mod tokamak

2019-04-10T17:53:49Z

Simulation of Hydrogen Generation from Methane Partial Oxidation in a Plasma Fuel Reformer

2019-04-10T20:22:40Z

Simulation of Hydrogen Generation from Methane Partial Oxidation in a Plasma Fuel Reformer Bel, N.; Heywood, J.B.; Bromberg, L.

Real Time Control of the Active MHD Diagnostic on Alcator C-Mod

2019-04-15T00:27:27Z

Real Time Control of the Active MHD Diagnostic on Alcator C-Mod Burke, W.; Cochran, W.; Snipes, J.; Sears, J.; Wolfe, S.; Zhong, X.

Plasmatron Reformation of Renewable Fuels

2019-04-15T00:27:27Z

Plasmatron Reformation of Renewable Fuels Bromberg, L.; Hadidi, K.; Cohn, D.R.

Active and Fast Particle Driven Alfven Eigenmodes in Alcator C-Mod

2019-04-10T17:53:47Z

Active and Fast Particle Driven Alfven Eigenmodes in Alcator C-Mod Snipes, J.A.; Basse, N.; Boswell, C.; Edlund, E.; Fasoli, A.; Gorelenkov, N.N.; Granetz, R.S.; Lin, L.; Lin, Y.; Parker, R.; Porkolab, M.; Sears, J.; Sharapov, S.; Tang, V.; Wukitch, S.

Role of trapped electron mode turbulence in internal transport barrier control in the Alcator C-Mod Tokamak

2019-04-10T17:53:47Z

Role of trapped electron mode turbulence in internal transport barrier control in the Alcator C-Mod Tokamak Ernst, D.; Bonoli, P.; Catto, P.; Dorland, W.; Fiore, C.; Granetz, R.; Greenwald, M.; Hubbard, A.; Porkolab, M.; Redi, M.; Rice, J.; Zhurovich, K.

Experimental Studies of Local and Global Emission Uniformity for a Magnetron Injection Gun

2019-04-10T17:53:48Z

Experimental Studies of Local and Global Emission Uniformity for a Magnetron Injection Gun Anderson, James; Temkin, Richard; Shapiro, Michael

Characterization of core and edge turbulence in L- and enhanced D-alpha H-mode Alcator C-Mod plasmas

2019-04-10T17:53:49Z

Characterization of core and edge turbulence in L- and enhanced D-alpha H-mode Alcator C-Mod plasmas Basse, N.P.; Edlund, E.M.; Ernst, D.R.; Fiore, C.L.; Greenwald, M.J.; Hubbard, A.E.; Hughes, J.W.; Irby, J.H.; Kramer, G.J.; Lin, L.; Lin, Y.; Marmar, E.S.; Mikkelsen, D.R.; Mossessian, D.A.; Porkolab, M.; Rice, J.E.; Snipes, J.A.; Stillerman, J.A.

Plasma Profiles & Flows in the High-Field Side Scrape-off Layer in Alcator C-Mod

2019-04-15T00:27:25Z

Plasma Profiles & Flows in the High-Field Side Scrape-off Layer in Alcator C-Mod Smick, N.; Bombard, B.; Pitcher, C.S.

Drift Kinetic Equation Exact Through Second Order in Gyro-Radius Expansion

2019-04-11T00:44:44Z

Drift Kinetic Equation Exact Through Second Order in Gyro-Radius Expansion Simakov, Andrei; Catto, Peter

The Dependence of Core Rotation on Magnetic Configuration and the Relation to the H-mode Power Threshold in Alcator C-Mod Plasmas with No Momentum Input

2019-04-09T18:57:01Z

The Dependence of Core Rotation on Magnetic Configuration and the Relation to the H-mode Power Threshold in Alcator C-Mod Plasmas with No Momentum Input Rice, J.E.; Hubbard, A.E.; Hughes, J.W.; Greenwald, M.J.; Bombard, B.; Irby, J.H.; Lin, Y.; Marmar, E.S.; Mossessian, D.; Wolfe, S.M.; Wukitch, S.J.

Transport-driven scrape-off layer flows and the x-point dependence of the L-H power threshold in Alcator C-Mod

2019-04-15T00:27:26Z

Transport-driven scrape-off layer flows and the x-point dependence of the L-H power threshold in Alcator C-Mod Bombard, B.; Rice, J.E.; Hubbard, A.E.; Hughes, J.W.; Greenwald, M.; Granetz, R.S.; Irby, J.H.; Lin, Y.; Lipschultz, B.; Marmar, E.S.; Marr, K.; Mossessian, D.; Parker, R.; Rowan, W.; Smick, N.; Snipes, J.A.; Terry, J.L.; Wolfe, S.M.; Wukitch, S.J.

DIVIMP modeling of impurity flows and screening in Alcator C-Mod

2019-04-10T16:35:48Z

DIVIMP modeling of impurity flows and screening in Alcator C-Mod Chung, T.; Hutchinson, I.H.; Lipschultz, B.; Bombard, B.; Lisgo, S.

Spectroscopic measurements of plasma flow in the SOL in C-Mod

2019-04-15T00:27:24Z

Spectroscopic measurements of plasma flow in the SOL in C-Mod Marr, K.; Lipschultz, B.; Bombard, B.; Terry, J.L.

Current Drive by Electron Bernstein Waves in Spherical Tokamaks

2019-04-11T00:44:47Z

Current Drive by Electron Bernstein Waves in Spherical Tokamaks Decker, J.; Ram, A.K.; Bers, A.; Peysson, Y.; Davies, C.N.; Cairns, R.A.; Taylor, G.; Efthimion, P.C.

Hydrogen-Rich Gas Production from Plasmatron Reforming of Biofuels

2019-04-11T00:44:46Z

Hydrogen-Rich Gas Production from Plasmatron Reforming of Biofuels Hadidi, K.; Bromberg, L.; Cohn, D.R.; Rabinovich, A.; Alexeev, N.; Samokhin, A.

Fluid Formalism for Collisionless Magnetized Plasmas

2019-04-12T21:43:04Z

Fluid Formalism for Collisionless Magnetized Plasmas Ramos, J.J.

Evaluation of the Neoclassical Radial Electric Field in a Collisional Tokamak

2019-04-12T21:43:03Z

Evaluation of the Neoclassical Radial Electric Field in a Collisional Tokamak Catto, Peter; Simakov, Andrei

MECO Transport Solenoid

2019-04-12T21:43:03Z

MECO Transport Solenoid Titus, Peter

Structural Analysis of the JET TAE Antenna

2019-04-11T00:44:46Z

Structural Analysis of the JET TAE Antenna Titus, Peter

Scrape-off layer flows, magnetic topology and influence on the L-H threshold in a tokamak

2019-04-11T00:44:46Z

Scrape-off layer flows, magnetic topology and influence on the L-H threshold in a tokamak Bombard, B.; Rice, J.E.; Hubbard, A.E.; Hughes, J.W.; Greenwald, M.; Granetz, R.S.; Irby, J.H.; Lin, Y.; Lipschultz, B.; Marmar, E.S.; Marr, K.; Mossessian, D.; Parker, R.; Rowan, W.; Smick, N.; Wolfe, S.M.; Wukitch, S.J.

Molten salt dynamics in glass melts using millimeter-wave emissivity measurements

2019-04-15T00:27:38Z

Molten salt dynamics in glass melts using millimeter-wave emissivity measurements Woskov, P.P.; Sundaram, S.K.; Daniel, W.E.; Miller, Don

Full Wave Simulations of Fast Wave Mode Conversion and Lower Hybrid Wave Propagation in Tokamaks

2019-04-15T00:27:38Z

Full Wave Simulations of Fast Wave Mode Conversion and Lower Hybrid Wave Propagation in Tokamaks Wright, J.C.; Bonoli, P.T.; Brambilla, M.; Meo, F.; Azevedo, E.; Batchelor, D.B.; Jaeger, E.F.; Berry, L.A.; Phillips, C.K.; Pletzer, A.

Study of Recycling Impurity Retention in Alcator C-Mod

2019-04-10T16:37:23Z

Study of Recycling Impurity Retention in Alcator C-Mod Chung, Taekyun

Design of an ICRF Fast Matching System on Alcator C-Mod

2019-04-10T17:53:51Z

Design of an ICRF Fast Matching System on Alcator C-Mod Parisot, A.

Conception of Thermal Far-Infrared Collective Thomson Scattering and Its Evolution to Gyrotron Scattering on JET/TEXTOR/ASDEX Upgrade

2019-04-09T15:24:31Z

Conception of Thermal Far-Infrared Collective Thomson Scattering and Its Evolution to Gyrotron Scattering on JET/TEXTOR/ASDEX Upgrade Woskov, Paul

Measuring shock-bang timing and rR evolution of D3He implosions at OMEGA

2019-04-11T00:44:45Z

Measuring shock-bang timing and rR evolution of D3He implosions at OMEGA Frenje, J.A.; Li, C.K.; Seguin, F.H.; Deciantis, J.; Kurebayashi, S.; Rygg, J.R.; Petrasso, R.D.; Delettrez, J.; Glebov, V.; Stoeckl, C.; Marshall, F.J.; Meyerhofer, D.D.; Sangster, T.C.; Smalyuk, V.A.; Soures, J.M.

Description of the TF Magnet and FIRE-SCSS (FIRE-6) Design Concept

2019-04-15T00:27:33Z

Description of the TF Magnet and FIRE-SCSS (FIRE-6) Design Concept Schultz, Joel; Radovinsky, Alexi; Titus, Peter

Millimeter-wave measurements at 137 GHz of DWPF black frit glass flow and salt layer pooling in a pilot scale melter

2019-04-15T00:27:33Z

Millimeter-wave measurements at 137 GHz of DWPF black frit glass flow and salt layer pooling in a pilot scale melter Woskov, Paul; Sundaram, S.K.; Daniel, Gene; Miller, Don; Harden, John

High-field side scrape-off layer density profiles inferred from Da emission on Alcator C-Mod

2019-04-15T00:27:38Z

High-field side scrape-off layer density profiles inferred from Da emission on Alcator C-Mod Boswell, C.J.; Terry, J.L.; Bombard, B.; Lipschultz, B.; Pitcher, C.S.

Overview of the Alcator C-Mod Program

2019-04-10T17:53:41Z

Overview of the Alcator C-Mod Program Greenwald, M.; Andelin, D.; Basse, N.; Bernabei, S.; Bonoli, P.; Boswell, C.; Bravenec, R.; Carreras, B.; Cziegler, I.; Edlund, E.; Ernst, D.; Fasoli, C.; Ferrara, M.; Fiore, C.; Granetz, R.; Grulke, O.; Hender, T.

Study of intermittent small-scale turbulence in Wendelstein 7-AS plasmas during controlled confinement transitions

2019-04-10T17:53:50Z

Study of intermittent small-scale turbulence in Wendelstein 7-AS plasmas during controlled confinement transitions Basse, N.P.; Zoletnik, S.; Michelsen, P.K.

Small-angle scattering theory revisited: Photocurrent and spatial localization

2019-04-10T17:53:50Z

Small-angle scattering theory revisited: Photocurrent and spatial localization Basse, N.P.; Zoletnik, S.; Michelsen, P.K.

Active and fast particle driven Alfvén eigenmodes in Alcator C-Mod

2019-04-15T00:27:32Z

Active and fast particle driven Alfvén eigenmodes in Alcator C-Mod Snipes, J.A.; Basse, N.; Boswell, C.; Edlund, E.; Fasoli, A.; Gorelenkov, N.N.; Granetz, R.S.; Lin, L.; Lin, Y.; Parker, R.; Porkolab, M.; Sears, J.; Sharapov, S.; Tang, V.; Wukitch, S.

ICRF loading studies on Alcator C-Mod

2019-04-10T17:53:41Z

ICRF loading studies on Alcator C-Mod Parisot, A.; Wukitch, S.J.; Bonoli, P.; Hughes, J.W.; Bombard, B.; Lin, Y.; Parker, R.; Porkolab, M.; Ram, A.K.

Internal Transport Barrier Production and Control in Alcator C-Mod

2019-04-15T00:27:32Z

Internal Transport Barrier Production and Control in Alcator C-Mod Fiore, C.L.; Bonoli, P.T.; Ernst, D.R.; Greenwald, M.J.; Marmar, E.S.; Redi, M.H.; Rice, J.E.; Wukitch, S.J.; Zhurovich, K.

Second Harmonic Operation at 460 GHz and Broadband Continuous Frequency Tuning of a Gyrotron Oscillator

2019-04-15T00:27:32Z

Second Harmonic Operation at 460 GHz and Broadband Continuous Frequency Tuning of a Gyrotron Oscillator Hornstein, M.K.; Bajaj, V.S.; Griffin, R.G.; Kreischer, K.E.; Mastovsky, I.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.

Effects of hot electrons on the stability of a closed field line plasma

2019-04-15T00:27:32Z

Effects of hot electrons on the stability of a closed field line plasma Krasheninnikova, Natalia; Catto, Peter

Ion Collection by a Sphere in a Flowing Plasma: 3. Floating Potential and Drag Force

2019-04-15T00:27:37Z

Ion Collection by a Sphere in a Flowing Plasma: 3. Floating Potential and Drag Force Hutchinson, I.H.

Seismic Analysis of the National Compact Stellerator Experiment (NCSX)

2019-04-15T00:27:32Z

Seismic Analysis of the National Compact Stellerator Experiment (NCSX) Titus, Peter

Electrostatic Fields in Density Cavities and Nonlinear Energization of Ions

2019-04-15T00:27:37Z

Electrostatic Fields in Density Cavities and Nonlinear Energization of Ions Ram, A.K.; Strozzi, D.J.; Bers, A.

A Drift Ordered Short Mean Free Path Description for Magnetized Plasma Allowing Strong Spatial Anisotropy

2019-04-11T00:44:45Z

A Drift Ordered Short Mean Free Path Description for Magnetized Plasma Allowing Strong Spatial Anisotropy Catto, P.J.; Simakov, A.N.

Controlling Edge Plasma Rotation Through Poloidally Localized Refueling

2019-04-09T17:34:12Z

Controlling Edge Plasma Rotation Through Poloidally Localized Refueling Helander, P.; Fulop, T.; Catto, P.J.

Ultrahigh Resolution Simulations of Mode Converted Ion Cyclotron Waves and Lower Hybrid Waves

2019-04-11T00:44:45Z

Ultrahigh Resolution Simulations of Mode Converted Ion Cyclotron Waves and Lower Hybrid Waves Wright, J.C.; Bonoli, P.T.; Azevedo, E.; Brambilla, M.

Investigation of Performance Limiting Phenomena in a Variable Phase ICRF Antenna in Alcator C-Mod

2019-04-11T00:44:45Z

Investigation of Performance Limiting Phenomena in a Variable Phase ICRF Antenna in Alcator C-Mod Wukitch, S.J.; Boivin, R.L.; Bonoli, P.T.; Goetz, J.A.; Irby, J.; Hutchinson, I.H.; Lin, Y.; Parisot, A.; Porkolab, M.; Marmar, E.; Schilling, G.; Wilson, J.R.

Using nuclear data and Monte-Carlo techniques to study areal density and mix in D 2 implosions

2019-04-09T16:44:19Z

Using nuclear data and Monte-Carlo techniques to study areal density and mix in D 2 implosions Kurebayashi, S.; Frenje, J.A.; Seguin, F.H.; Rygg, J.R.; Li, C.K.; Petrasso, R.D.; Glebov, V.; Delettrez, J.A.; Sangster, T.C.; Meyerhofer, D.D.; Stoeckl, C.; Soures, J.M.; Amendt, P.A.; Hatchett, S.P.; Turner, R.E.

Transport-Driven Scrape-off Layer Flows and the Boundary Conditions Imposed at the Magnetic Separatrix in a Tokamak Plasma

2019-04-15T00:27:37Z

Transport-Driven Scrape-off Layer Flows and the Boundary Conditions Imposed at the Magnetic Separatrix in a Tokamak Plasma Bombard, B.; Rice, J.E.; Hubbard, A.E.; Hughes, J.W.; Greenwald, M.; Irby, J.; Lin, Y.; Lipschultz, B.; Marmar, E.S.; Pitcher, C.S.; Smick, N.; Wolfe, S.M.; Wukitch, S.J.

Effects of Nonuniform Illumination on Implosion Asymmetry in Direct-Drive Inertial Confinement Fusion

2019-04-09T15:54:28Z

Effects of Nonuniform Illumination on Implosion Asymmetry in Direct-Drive Inertial Confinement Fusion Li, C.K.; Seguin, F.H.; Frenje, J.A.; Petrasso, R.D.; Delettrez, J.A.; Kenty, P.W.; Sangster, T.C.; Keck, R.L.; Soures, J.M.; Marshall, F.J.; Meyerhofer, D.D.; Goncharov, V.N.; Knauer, J.P.; Radha, P.B.; Regan, S.P.; Seka, W.

Study of Laser Plasma Interactions Using an Eulerian Vlasov Code

2019-04-15T00:27:37Z

Study of Laser Plasma Interactions Using an Eulerian Vlasov Code Strozzi, D.J.; Shoucri, M.M.; Bers, A.

Studies of the 1.5-MW, 110-GHz Gyrotron Experiment

2019-04-15T00:27:37Z

Studies of the 1.5-MW, 110-GHz Gyrotron Experiment Shapiro, M.; Temkin, R.; Mastovsky, I.; Cauffman, S.

Plasma Catalytic Reforming of Biofuels

2019-04-15T00:27:36Z

Plasma Catalytic Reforming of Biofuels Hadidi, K.; Bromberg, L.; Cohn, D.R.; Rabinovich, A.; Alexeev, N.; Samokhin, A.

Impurity Plume Experiments in the Edge Plasma of the Alcator C-Mod Tokamak

2019-04-15T00:27:36Z

Impurity Plume Experiments in the Edge Plasma of the Alcator C-Mod Tokamak Gangadhara, S.; Bombard, B.

Spin Stability of Asymmetrically Charged Plasma Dust

2019-04-15T00:27:36Z

Spin Stability of Asymmetrically Charged Plasma Dust Hutchinson, I.H.

Stopping of Directed Energetic Electrons in High-Temperature Hydrogenic Plasmas

2019-04-15T00:27:36Z

Stopping of Directed Energetic Electrons in High-Temperature Hydrogenic Plasmas Li, C.K.; Petrasso, R.D.

Hydrogen generation from plasmatron reformers: A promising technology for NO[subscript x] adsorber regeneration and other automotive applications

2019-04-09T19:09:48Z

Hydrogen generation from plasmatron reformers: A promising technology for NO[subscript x] adsorber regeneration and other automotive applications Bromberg, L.; Crane, S.; Rabinovich, A.; Kong, Y.; Cohn, D.R.; Heywood, J.; Alexeev, N.; Samokhin, A.

Toroidal Rotation and Momentum Transport in Alcator C-Mod Plasmas with No Momentum Input

2019-04-15T00:27:34Z

Toroidal Rotation and Momentum Transport in Alcator C-Mod Plasmas with No Momentum Input Rice, J.E.; Lee, W.D.; Marmar, E.S.; Basse, N.P.; Bonoli, P.T.; Greenwald, M.J.; Hubbard, A.E.; Hughes, J.W.; Hutchinson, I.H.; Cushman, A.; Irby, J.H.; Lin, Y.; Mossessian, D.; Snipes, J.A.; Wolfe, S.M.; Wukitch, S.J.; Zhurovich, K.

A Study of JET SOL Radial Transport Based on Particle Balance

2019-04-15T00:27:34Z

A Study of JET SOL Radial Transport Based on Particle Balance Lipschultz, B.; Andrew, P.; Coad, J.; Erents, K.; Felton, R.; Fundamenski, W.; Hidalgo, C.; Huber, A.; Bombard, B.; Matthews, G.; Mertens, P.; Pitts, R.A.; Silva, C.; Stamp, M.; Strachan, J.; Whyte, D.

Investigation of ICRF Mode Conversion at the Ion-ion Hybrid in Alcator C-Mod

2019-04-15T00:27:35Z

Investigation of ICRF Mode Conversion at the Ion-ion Hybrid in Alcator C-Mod Lin, Y.; Wukitch, S.J.; Bonoli, P.T.; Melby, E.; Porkolab, M.; Wright, J.C.; Basse, N.; Hubbard, A.E.; Irby, J.; Lin, L.; Marmar, E.S.; Mazurenko, A.; Mossessian, D.; Parisot, A.; Rice, J.; Wolfe, S.; Phillips, C.K.; Schilling, G.; Wilson, J.R.; Phillips, P.

Control of Internal Transport Barriers on Alcator C-Mod

2019-04-15T00:27:35Z

Control of Internal Transport Barriers on Alcator C-Mod Fiore, C.L.; Bonoli, P.T.; Ernst, D.R.; Hubbard, A.E.; Greenwald, M.J.; Lynn, A.; Marmar, E.S.; Phillips, P.; Redi, M.H.; Rice, J.E.; Wolfe, S.M.; Wukitch, S.J.; Zhurovich, K.

Initial Active MHD Spectroscopy Experiments Exciting Stable Alfven Eigenmodes in Alcator C-Mod

2019-04-15T00:27:35Z

Initial Active MHD Spectroscopy Experiments Exciting Stable Alfven Eigenmodes in Alcator C-Mod Snipes, J.A.; Schmittdiel, D.; Fasoli, A.; Granetz, R.S.; Parker, R.R.

Local Threshold Conditions and Fast Transition Dynamics of the L-H Transition on Alcator C-Mod

2019-04-10T17:53:51Z

Local Threshold Conditions and Fast Transition Dynamics of the L-H Transition on Alcator C-Mod Hubbard, Amanda; Carreras, Benjamin; Basse, Nils; Negrete, Diego; Hughes, Jerry; Lynn, Alan; Marmar, Earl; Mossessian, Dmitri; Phillips, Perry; Wukitch, Steven

Observations of Anomalous Momentum Transport in Alcator C-Mod Plasmas with No Momentum Input

2019-04-09T19:09:35Z

Observations of Anomalous Momentum Transport in Alcator C-Mod Plasmas with No Momentum Input Rice, J.E.; Lee, W.D.; Marmar, E.S.; Bonoli, P.T.; Granetz, R.S.; Greenwald, M.J.; Hubbard, A.E.; Hutchinson, I.H.; Irby, J.H.; Lin, Y.; Mossessian, D.; Snipes, J.A.; Wolfe, S.M.; Wukitch, S.J.

ECCD for Advanced Tokamak Operations Fisch-Boozer versus Ohkawa Methods

2019-04-09T17:59:33Z

ECCD for Advanced Tokamak Operations Fisch-Boozer versus Ohkawa Methods Decker, J.

Electron Cyclotron Current Drive by the Ohkawa Method in the Presence of Bootstrap Current

2019-04-09T19:15:54Z

Electron Cyclotron Current Drive by the Ohkawa Method in the Presence of Bootstrap Current Decker, J.; Bers, A.; Ram, A.K.; Peysson, Y.

Beyond Benchmarking - How Experiments and Simulations Can Work Together in Plasma Physics

2019-04-15T00:27:33Z

Beyond Benchmarking - How Experiments and Simulations Can Work Together in Plasma Physics Greenwald, M.

Drift-Ordered Fluid Equations for Field-Aligned Modes in Low-β Collisional Plasma with Equilibrium Pressure Pedestals

2019-04-10T16:53:21Z

Drift-Ordered Fluid Equations for Field-Aligned Modes in Low-β Collisional Plasma with Equilibrium Pressure Pedestals Simakov, Andrei; Catto, Peter

Excitation and Emission of Electron Cyclotron Waves in Spherical Tori

2019-04-10T17:53:39Z

Excitation and Emission of Electron Cyclotron Waves in Spherical Tori Ram, A.K.; Bers, A.

Drift Ballooning Instabilities in Tokamak Edge Plasmas

2019-04-15T00:27:31Z

Drift Ballooning Instabilities in Tokamak Edge Plasmas Hastie, R.J.; Ramos, J.J.; Porcelli, F.

Coherent Acceleration of Magnetized Ions by Electrostatic Waves With Arbitrary Wavenumbers

2019-04-15T00:27:31Z

Coherent Acceleration of Magnetized Ions by Electrostatic Waves With Arbitrary Wavenumbers Strozzi, D.J.; Ram, A.K.; Bers, A.

Structural Design of High Field Tokamaks

2019-04-11T00:44:44Z

Structural Design of High Field Tokamaks Titus, Peter

Observations of Anomalous Momentum Transport in Tokamak Plasmas with No Momentum Input

2019-04-15T00:27:30Z

Observations of Anomalous Momentum Transport in Tokamak Plasmas with No Momentum Input Lee, W.D.; Rice, J.E.; Marmar, E.S.; Greenwald, M.J.; Hutchinson, I.H.; Snipes, J.A.

X-ray Spectroscopy of High n Transitions of He- and Ne-like Ions in Alcator C-Mod Plasmas

2019-04-15T00:27:24Z

X-ray Spectroscopy of High n Transitions of He- and Ne-like Ions in Alcator C-Mod Plasmas Rice, J.E.; Fournier, K.B.; Marmar, E.S.; Terry, J.L.; Safronova, U.I.

Magnet Structural Design For The Fusion Ignition Research Experiment (FIRE)

2019-04-15T00:27:30Z

Magnet Structural Design For The Fusion Ignition Research Experiment (FIRE) Titus, Peter

Creep Effects in the Toroidal Field Coils of Fire and Other Burning Plasma Tokamaks

2019-04-09T18:06:38Z

Creep Effects in the Toroidal Field Coils of Fire and Other Burning Plasma Tokamaks Titus, Peter; Salvetti, Matteo

Ion Cyclotron Range of Frequencies Mode Conversion Electron Heating in Deuterium-Hydrogen Plasmas in the Alcator C-Mod Tokamak

2019-04-10T17:53:42Z

Ion Cyclotron Range of Frequencies Mode Conversion Electron Heating in Deuterium-Hydrogen Plasmas in the Alcator C-Mod Tokamak Lin, Y.; Wukitch, S.J.; Bonoli, P.T.; Marmar, E.; Mossessian, D.; Melby, E.; Phillips, P.; Porkolab, M.; Schilling, G.; Wolfe, S.; Wright, J.

Superconducting options for final optics magnets for the Heavy Ion Driver in Inertial Fusion Energy

2019-04-10T19:20:22Z

Superconducting options for final optics magnets for the Heavy Ion Driver in Inertial Fusion Energy Bromberg, L.

Pressure Profile Control of Internal Transport Barrier Plasmas in Alcator C-Mod

2019-04-09T16:41:39Z

Pressure Profile Control of Internal Transport Barrier Plasmas in Alcator C-Mod Rice, J.E.; Bonoli, P.T.; Fiore, C.L.; Lee, W.D.; Marmar, E.S.; Wukitch, S.J.; Granetz, R.S.; Hubbard, A.E.; Hughes, J.W.; Irby, J.H.; Lin, Y.; Mossessian, D.; Wolfe, S.M.; Zhurovich, K.; Greenwald, M.J.; Hutchinson, I.H.; Porkolab, M.; Snipes, J.A.

Asymptotic analysis of dispersion characteristics in two-dimensional metallic photonic band gap structures.

2019-04-10T07:30:47Z

Asymptotic analysis of dispersion characteristics in two-dimensional metallic photonic band gap structures. Smirnova, Evgenya; Chen, Chipeng

Helium Catalyzed D-D Fusion in a Levitated Dipole In a Z-Pinch

2019-04-10T17:53:44Z

Helium Catalyzed D-D Fusion in a Levitated Dipole In a Z-Pinch Kesner, J.; Garnier, D.T.; Hansen, A.; Mauel, M.; Bromberg, L.

Observations of the Turbulence in the Scrape-Off-Layers of Alcator C-Mod and NSTX and Comparisons With Simualtion

2019-04-12T14:48:23Z

Observations of the Turbulence in the Scrape-Off-Layers of Alcator C-Mod and NSTX and Comparisons With Simualtion Terry, J.L.; Zweben, S.J.; Hallatschek, K.; Bombard, B.; Maqueda, R.J.; Bai, B.; Boswell, C.J.; Greenwald, M.; Kopon, D.; Nevins, W.M.; Pitcher, C.S.; Rogers, B.N.; Stotler, D.P.; Xu, X.Q.

Design and emission uniformity studies of a 1.5-MW gyrotron electron gun

2019-04-10T07:18:50Z

Design and emission uniformity studies of a 1.5-MW gyrotron electron gun Anderson, J.P.; Korby, S.E.; Temkin, R.J.; Shapiro, M.A.; Felch, K.L.; Cauffman, S.

Convective Cell Formation In a Z-Pinch

2019-04-12T14:48:22Z

Convective Cell Formation In a Z-Pinch Kesner, J.

H-mode edge stability of Alcator C-mod plasmas

2019-04-12T14:48:22Z

H-mode edge stability of Alcator C-mod plasmas Mossessian, D.A.; Snyder, P.; Hubbard, A.; Hughes, J.W.; Greenwald, M.; Bombard, B.; Snipes, J.A.; Wolfe, S.; Wilson, H.

Image-charge effects on the envelope dynamics of an unbunched intense charged-particle beam

2019-04-11T04:24:05Z

Image-charge effects on the envelope dynamics of an unbunched intense charged-particle beam Qian, B.L.; Zhou, J.; Chen, C.

Edge dimensionless identity experiment on DIII-D and Alcator C-Mod

2019-04-10T19:50:17Z

Edge dimensionless identity experiment on DIII-D and Alcator C-Mod Mossessian, D.A.; Groebner, R.J.; Moyer, R.A.; Osborne, T.H.; Hughes, J.W.; Greenwald, M.; Hubbard, A.; Rhodes, T.L.

Onboard Plasmatron Generation of Hydrogen Rich Gas for Diesel Engine Exhaust Aftertreatment and Other Applications

2019-04-11T04:24:14Z

Onboard Plasmatron Generation of Hydrogen Rich Gas for Diesel Engine Exhaust Aftertreatment and Other Applications Bromberg, L.; Cohn, D.R.; Heywood, J.; Rabinovich, A.

Studies of Stimulated Raman Scattering in Laser Plasma Interactions

2019-04-12T14:48:21Z

Studies of Stimulated Raman Scattering in Laser Plasma Interactions Salcedo, A.; Focia, R.; Ram, A.; Bers, A.

Resistive MHD Transport Model for an RFP: Part II - Results

2019-04-11T04:51:16Z

Resistive MHD Transport Model for an RFP: Part II - Results Bruno, A.; Freidberg, J.P.; Hastie, R.J.

Resistive MHD Transport Model for an RFP: Part I - The Model

2019-04-11T04:51:13Z

Resistive MHD Transport Model for an RFP: Part I - The Model Bruno, A.; Freidberg, J.P.; Hastie, R.J.

Overview of Recent Alcator C-Mod Research

2019-04-12T14:48:22Z

Overview of Recent Alcator C-Mod Research Marmar, E.S.; Bai, B.; Boivin, R.L.; Bonoli, P.T.; Boswell, C.; Bravenec, R.; Carreras, B.; Ernst, D.; Fiore, C.; Gangadhara, S.; Gentle, K.; Goetz, J.; Granetz, R.; Greenwald, M.; Hallatschek, K.; Hastie, J.; Hosea, J.; Hubbard, A.; Hughes, J.W.; Hutchinson, I.; In, Y.

General Proof of Symmetry Relations in Mode Conversion with Application to, Excitation of, and Emission from, Electron Bernstein Waves

2019-04-12T14:48:21Z

General Proof of Symmetry Relations in Mode Conversion with Application to, Excitation of, and Emission from, Electron Bernstein Waves Bers, A.; Ram, A.

Studies of Stimulated Raman Scattering in Laser Plasma Interactions

2019-04-12T14:48:21Z

Studies of Stimulated Raman Scattering in Laser Plasma Interactions Salcedo, A.; Focia, R.J.; Ram, A.K.; Bers, A.

Electron Bernstein Waves in Spherical Tori

2019-04-11T04:24:21Z

Electron Bernstein Waves in Spherical Tori Ram, A.; Bers, A.

Symmetries in Dissipation-Free Linear Mode Conversion

2019-04-11T04:22:27Z

Symmetries in Dissipation-Free Linear Mode Conversion Bers, A.; Ram, A.

On Synergism between Bootstrap and Radio-Frequency Driven Currents

2019-04-11T04:51:12Z

On Synergism between Bootstrap and Radio-Frequency Driven Currents Decker, J.; Peysson, Y.; Bers, A.; Ram, A.

Symmetries in Dissipation-Free Linear Mode Conversion

2019-04-12T14:48:21Z

Symmetries in Dissipation-Free Linear Mode Conversion Bers, A.; Ram, A.

Toroidal rotation as an explanation for plasma flow observations in the Alcator C-Mod scrape-off layer

2019-04-15T00:27:23Z

Toroidal rotation as an explanation for plasma flow observations in the Alcator C-Mod scrape-off layer Bombard, Brian

Flow measurements in the Scrape-Off Layer of Alcator C-Mod using Impurity Plumes

2019-04-09T17:05:59Z

Flow measurements in the Scrape-Off Layer of Alcator C-Mod using Impurity Plumes Gangadhara, S.; Bombard, B.

Effects of poloidal variation of neutral density on Pfirsch-Schlüter transport near tokamak edge

2019-04-10T17:53:44Z

Effects of poloidal variation of neutral density on Pfirsch-Schlüter transport near tokamak edge Simakov, A.N.; Catto, P.J.

Thermal return reflection method for resolving emissivity and temperature in radiometric measurements

2019-04-11T04:24:21Z

Thermal return reflection method for resolving emissivity and temperature in radiometric measurements Woskov, P.P.; Sundaram, S.K.

Thomson scattering upgrades on Alcator C-Mod

2019-04-10T17:53:43Z

Thomson scattering upgrades on Alcator C-Mod Hughes, J.W.; Mossessian, D.; Zhurovich, K.; Maria, M.; Jensen, K.; Hubbard, A.

Resistive stability of magnetic dipole and other axisymmetric closed field line configurations

2019-04-10T17:53:43Z

Resistive stability of magnetic dipole and other axisymmetric closed field line configurations Simakov, A.N.; Catto, P.J.; Ramos, J.J.; Hastie, R.J.

Electron Cyclotron Resonance Heating of Plasmas in Spherical Tori

2019-04-12T14:48:20Z

Electron Cyclotron Resonance Heating of Plasmas in Spherical Tori Ram, A.; Bers, A.

Effect of poloidal density variation of neutral atoms on the tokamak edge

2019-04-15T00:27:23Z

Effect of poloidal density variation of neutral atoms on the tokamak edge Fulop, T.; Helander, P.; Catto, Peter

An interpretation of fluctuation induced transport derived from electrostatic probe measurements

2019-04-15T00:27:22Z

An interpretation of fluctuation induced transport derived from electrostatic probe measurements Bombard, B.

Observations and Empirical Scalings of the High-Confinement Mode Pedestal on Alcator C-Mod

2019-04-15T00:27:23Z

Observations and Empirical Scalings of the High-Confinement Mode Pedestal on Alcator C-Mod Hughes, J.W.; Mossessian, D.A.; Hubbard, A.E.; Bombard, B.; Marmar, E.S.

H-Mode Pedestal Characteristics and MHD Stability of the Edge Plasma in Alcator C-Mod

2019-04-10T17:53:43Z

H-Mode Pedestal Characteristics and MHD Stability of the Edge Plasma in Alcator C-Mod Mossessian, D.A.; Snyder, P.B.; Greenwald, M.; Hughes, J.W.; Lin, Y.; Mazurenko, A.; Medvedev, S.; Wilson, H.R.; Wolfe, S.

Large Electrodless Plasmas at Atmospheric Pressure Sustained by a Microwave Waveguide

2019-04-09T19:26:47Z

Large Electrodless Plasmas at Atmospheric Pressure Sustained by a Microwave Waveguide Woskov, Paul; Hadidi, Kamal

Investigation of the origin of neutrals in the main chamber of Alcator C-Mod

2019-04-15T00:27:23Z

Investigation of the origin of neutrals in the main chamber of Alcator C-Mod Lipschultz, B.; Bombard, B.; Pitcher, C.S.; Boivin, R.

Ion Collection by a Sphere in a Flowing Plasma: 1. Quasineutral

2019-04-09T16:29:37Z

Ion Collection by a Sphere in a Flowing Plasma: 1. Quasineutral Hutchinson, I.H.

Millimeter-Wave Monitoring of Nuclear Waste Glass Melts – An Overview

2019-04-15T00:27:22Z

Millimeter-Wave Monitoring of Nuclear Waste Glass Melts – An Overview Woskov, P.P.; Machuzak, J.S.; Thomas, P.; Sundaram, S.K.; Daniel, William

Electron Bernstein Waves Heating and Emission in Spherical Tokamaks

2019-04-11T04:24:20Z

Electron Bernstein Waves Heating and Emission in Spherical Tokamaks Ram, A.K.; Bers, A.

Double transport barrier experiments on Alcator C-Mod

2019-04-11T04:24:20Z

Double transport barrier experiments on Alcator C-Mod Wukitch, S.J.; Boivin, R.L.; Bonoli, P.T.; Fiore, C.L.; Granetz, R.S.; Greenwald, M.J.; Hubbard, A.E.; Hutchinson, I.H.; In, Y.; Irby, J.; Lin, Y.; Marmar, E.S.; Mossessian, D.; Porkolab, M.; Schilling, G.; Rice, J.E.; Snipes, J.A.; Wolfe, S.M.

Emission of Electron Bernstein Waves

2019-04-11T04:24:20Z

Emission of Electron Bernstein Waves Ram, A.K.; Bers, A.; Taylor, G.; Efthimion, P.

Emission of Electron Bernstein Waves in Plasmas

2019-04-12T14:48:20Z

Emission of Electron Bernstein Waves in Plasmas Ram, A.K.; Bers, A.; Davies, C.N.

Density Limits in Toroidal Plasmas

2019-04-09T18:22:35Z

Density Limits in Toroidal Plasmas Greenwald, Martin

Electron Bernstein Waves in Spherical Tokamaks

2019-04-09T16:01:15Z

Electron Bernstein Waves in Spherical Tokamaks Ram, A.K.; Bers, A.; Davies, C.N.; Taylor, G.; Efthimion, P.

An Experimental and Theoretical Study of the "Quasi-Coherent Fluctuations" in a High Density Tokamak Plasma

2019-04-12T14:48:20Z

An Experimental and Theoretical Study of the "Quasi-Coherent Fluctuations" in a High Density Tokamak Plasma Mazurenko, A.; Porkolab, M.; Mossessian, D.; Snipes, J.A.; Xu, X.Q.; Nevins, W.M.

Equilibrium and confinement of bunched annular beams

2019-04-09T17:15:43Z

Equilibrium and confinement of bunched annular beams Hess, Mark; Chen, Chiping

Driven reconnection about a magnetic X-line with strong guide component

2019-04-11T04:24:18Z

Driven reconnection about a magnetic X-line with strong guide component Ramos, J.J.; Porcelli, F.; Verastegui, R.

Electrostatic Drift Modes in a Closed Field Line Configuration

2019-04-09T16:55:32Z

Electrostatic Drift Modes in a Closed Field Line Configuration Kesner, J.; Hastie, R.J.

Impurity Transport Studies in Tokamak Edge Plasmas Using Visible Imaging

2019-04-09T18:01:29Z

Impurity Transport Studies in Tokamak Edge Plasmas Using Visible Imaging Gangadhara, S.; Bombard, B.

Evolution of Pedestal Profiles through the L-H and H-L Transitions in Alcator C-Mod

2019-04-15T00:27:17Z

Evolution of Pedestal Profiles through the L-H and H-L Transitions in Alcator C-Mod Hubbard, A.E.; Carreras, B.; Boivin, R.L.; Hughes, J.W.; Marmar, E.S.; Mossessian, D.; Wukitch, S.

CompactPCI based Data acquisition with MDSplus

2019-04-12T14:48:19Z

CompactPCI based Data acquisition with MDSplus Stillerman, Joshua; Fredian, Thomas

Temperature Transients of Fusion-fission Hybrid Reactors in Loss of Coolant Accidents

2019-04-09T16:09:52Z

Temperature Transients of Fusion-fission Hybrid Reactors in Loss of Coolant Accidents Tang, Vincent; Parker, Ron

2D Images of Deuterium Emission in the Alcator C-Mod Tokamak Divertor

2019-04-10T17:53:34Z

2D Images of Deuterium Emission in the Alcator C-Mod Tokamak Divertor Boswell, Christopher; Terry, James

Beta Limiting MHD Activity and Mode Locking in Alcator C-Mod

2019-04-10T17:53:34Z

Beta Limiting MHD Activity and Mode Locking in Alcator C-Mod Snipes, J.A.; Granetz, R.S.; Hastie, R.J.; Hubbard, A.E.; In, Y.; Mossessian, D.; Rice, J.E.; Ramos, J.J.; Schmittdiel, D.; Taylor, G.; Wolfe, S.M.

The Invalidity of a Mach Probe Model

2019-04-12T14:48:20Z

The Invalidity of a Mach Probe Model Hutchinson, I.H.

Double Transport Barrier Plasmas in Alcator C-Mod

2019-04-09T15:51:09Z

Double Transport Barrier Plasmas in Alcator C-Mod Rice, J.E.; Bonoli, P.T.; Marmar, E.S.; Wukitch, S.J.; Boivin, R.L.; Fiore, C.L.; Granetz, R.S.; Greenwald, M.J.; Hubbard, A.E.; Hughes, J.W.; Hutchinson, I.H.; Irby, J.H.; Lin, Y.; Mossessian, D.; Porkolab, M.; Schilling, G.; Snipes, J.A.; Wolfe, S.M.

Simulation of Photonic Band Gaps in Metal Rod Lattices for Microwave Applications

2019-04-10T20:09:25Z

Simulation of Photonic Band Gaps in Metal Rod Lattices for Microwave Applications Smirnova, E.I.; Chen, C.; Shapiro, M.A.; Temkin, R.J.

Observation of Multiple Cascade Steps of the Langmuir Decay Instability in a Laser Plasma

2019-04-12T14:48:19Z

Observation of Multiple Cascade Steps of the Langmuir Decay Instability in a Laser Plasma Focia, R.J.; Montgomery, D.S.; Fernandez, J.C.; Johnson, R.P.

Homogeneous Charge Compression Ignition Control by the Use of Plasmatron Fuel Converter Technology

2019-04-12T14:48:19Z

Homogeneous Charge Compression Ignition Control by the Use of Plasmatron Fuel Converter Technology Bromberg, L.; Rabinovich, A.

Phase Retrieval of Gyrotron Beams Based on Irradiance Moments

2019-04-11T04:22:24Z

Phase Retrieval of Gyrotron Beams Based on Irradiance Moments Anderson, J.P.; Shapiro, M.A.; Temkin, R.J.; Denison, D.R.

MDSplus Current Developments and Future Directions

2019-04-11T04:22:25Z

MDSplus Current Developments and Future Directions Fredian, Thomas; Stillerman, Joshua

Global Photonic Band Gaps in Two-Dimensional Metallic Lattices

2019-04-12T14:48:19Z

Global Photonic Band Gaps in Two-Dimensional Metallic Lattices Smirnova, E.I.; Chen, C.

Equilibrium and Stability Properties of Self-Organized Electron Spiral Toroids

2019-04-11T04:22:23Z

Equilibrium and Stability Properties of Self-Organized Electron Spiral Toroids Chen, C.; Pakter, R.; Seward, D.C.

A Photonic Band Gap Resonator Gyrotron

2019-04-11T04:22:23Z

A Photonic Band Gap Resonator Gyrotron Sirigiri, J.R.; Kreischer, K.E.; Machuzak, J.; Mastovsky, I.; Shapiro, M.A.; Temkin, R.J.

Beam Confinement in Periodic Permanent Magnet Focusing Klystrons

2019-04-10T17:53:39Z

Beam Confinement in Periodic Permanent Magnet Focusing Klystrons Hess, Mark; Chen, Chiping

Stability of the Envelope Evolution of a Cold-Fluid Corkscrewing Elliptic Beam in a Uniform-Focusing Magnetic Field

2019-04-11T04:22:23Z

Stability of the Envelope Evolution of a Cold-Fluid Corkscrewing Elliptic Beam in a Uniform-Focusing Magnetic Field Roytershteyn, V.; Chen, C.; Pakter, R.

17 GHz Photonic Band Gap Cavity with Improved Input Coupling

2019-04-12T14:48:18Z

17 GHz Photonic Band Gap Cavity with Improved Input Coupling Shapiro, M.A.; Brown, W.J.; Mastovsky, I.; Sirigiri, J.R.; Temkin, R.J.

Phase Contrast Imaging of Ion Bernstein and Fast Waves in Alcator C-Mod

2019-04-09T18:58:57Z

Phase Contrast Imaging of Ion Bernstein and Fast Waves in Alcator C-Mod Melby, E.; Mazurenko, A.; Porkolab, M.; Bonoli, P.T.; Wukitch, S.J.

Electron Cyclotron Emission Refraction Effects during Edge Localized Modes

2019-04-10T07:12:50Z

Electron Cyclotron Emission Refraction Effects during Edge Localized Modes In, Y.; Hubbard, A.E.; Hutchinson, I.H.

The Quasi-Coherent Signature of Enhanced D [subscript alpha] H-mode in Alcator C-Mod

2019-04-15T00:27:21Z

The Quasi-Coherent Signature of Enhanced D [subscript alpha] H-mode in Alcator C-Mod Snipes, J.A.; Bombard, B.; Greenwald, M.; Hutchinson, I.H.; Irby, J.; Lin, Y.; Mazurenko, A.; Porkolab, M.

Stability criterion for edge-localized, high-n external modes in tokamaks

2019-04-15T00:27:21Z

Stability criterion for edge-localized, high-n external modes in tokamaks Ramos, J.J.; Verastegui, R.; Hastie, R.J.

Edge Ion Heating and Parametric Decay during Injection of Ion Cyclotron Resonance Frequency Power on the Alcator C-Mod Tokamak

2019-04-15T00:27:21Z

Edge Ion Heating and Parametric Decay during Injection of Ion Cyclotron Resonance Frequency Power on the Alcator C-Mod Tokamak Rost, J.C.; Porkolab, M.; Boivin, R.L.

Electronic Excitation Temperature Profiles in an Air Microwave Plasma Torch

2019-04-10T17:53:39Z

Electronic Excitation Temperature Profiles in an Air Microwave Plasma Torch Green, K.M.; Borras, M.C.; Woskov, P.P.; I, G.J.; Hadidi, K.; Thomas, P.

ARIES-AT Magnet Systems

2019-04-10T17:53:38Z

ARIES-AT Magnet Systems Bromberg, L.; Brown, T.; Dahlgren, F.; Heitzenroeder, P.

Particle transport in the scrape-off layer and its relationship to discharge density limit in Alcator C-Mod

2019-04-15T00:27:21Z

Particle transport in the scrape-off layer and its relationship to discharge density limit in Alcator C-Mod Bombard, B.; Boivin, R.L.; Greenwald, M.; Hughes, J.; Lipschultz, B.; Mossessian, D.; Pitcher, C.S.; Terry, J.L.; Zweben, S.J.

AC Loss Measurements of Sub-sized Nb[subscript 3]Sn CICC Cable with Transport Current

2019-04-15T00:27:20Z

AC Loss Measurements of Sub-sized Nb[subscript 3]Sn CICC Cable with Transport Current Alvey, Tim; Takayasu, Makoto; Minervini, Joseph

Pedestal profiles and fluctuations in C-Mod enhanced D-alpha H-modes

2019-04-10T17:53:38Z

Pedestal profiles and fluctuations in C-Mod enhanced D-alpha H-modes Hubbard, Amanda; Boivin, Rejean; Carreras, Benjamin; Granetz, Robert; Greenwald, Martin; Hughes, Jerry; Hutchinson, Ian; Irby, James; Klein, Veronica; Bombard, Brian; Lin, Yijun; Marmar, Earl; Mazurenko, A.; Mossessian, Dmitri

Hydrogen Manufacturing Using Low Current, Non-Thermal Plasma Boosted Fuel Converters

2019-04-10T17:53:38Z

Hydrogen Manufacturing Using Low Current, Non-Thermal Plasma Boosted Fuel Converters Bromberg, L.; Cohn, D.R.; Rabinovich, A.; Alexeev, N.

Application of Magnetically-Broadened Hydrogenic Line Profiles to Computational Modeling of a Plasma Experiment

2019-04-15T00:27:20Z

Application of Magnetically-Broadened Hydrogenic Line Profiles to Computational Modeling of a Plasma Experiment Adams, M.L.; Scott, H.A.; Lee, R.W.; Terry, J.L.; Marmar, E.S.; Lipschultz, B.; Pigarov, A.; Freidberg, J.P.

Enhanced D-Alpha H-mode Studies in the Alcator C-Mod Tokamak

2019-04-15T00:27:18Z

Enhanced D-Alpha H-mode Studies in the Alcator C-Mod Tokamak Marmar, E.; Boivin, R.L.; Fiore, C.; Goetz, J.; Granetz, R.; Greenwald, M.; Hubbard, A.; Hughes, J.; Hutchinson, I.; Irby, J.; Bombard, B.; Lin, Y.; Lipschultz, B.; Mazurenko, A.; Mossessian, D.; Pedersen, T.; Porkolab, M.; Rice, J.; Schilling, G.; Snipes, J.A.

Observations of Toroidal Rotation Suppression with ITB Formation in ICRF and Ohmic H-mode Alcator C-Mod Plasmas

2019-04-10T17:53:37Z

Observations of Toroidal Rotation Suppression with ITB Formation in ICRF and Ohmic H-mode Alcator C-Mod Plasmas Rice, J.; Boivin, R.; Bonoli, P.; Goetz, J.; Granetz, R.; Greenwald, M.; Hutchinson, I.; Marmar, E.; Snipes, J.; Wolfe, S.; Wukitch, S.; Fiore, C.; Irby, J.; Mossessian, D.; Porkolab, M.

Signature of Turbulent Zonal Flows Observed in the DIII-D Tokamak

2019-04-10T17:53:35Z

Signature of Turbulent Zonal Flows Observed in the DIII-D Tokamak Coda, S.; Porkolab, M.; Burrell, K.H.

Cross-Field Transport in the SOL: Its Relationship to Main Chamber and Divertor Neutral Control in Alcator C-Mod

2019-04-15T00:27:19Z

Cross-Field Transport in the SOL: Its Relationship to Main Chamber and Divertor Neutral Control in Alcator C-Mod Bombard, B.; Lipschultz, B.; Goetz, J.A.; Pitcher, C.S.; Asakura, N.; Boivin, R.L.; Hughes, J.W.; Kallenbach, A.; Cracken, G.M.; Matthews, G.F.; Mossessian, D.; Rice, J.E.; Terry, J.L.; Umansky, M.V.

Core internal transport barriers on Alcator C-Mod

2019-04-15T00:27:19Z

Core internal transport barriers on Alcator C-Mod Fiore, C.L.; Rice, J.E.; Bonoli, P.T.; Boivin, R.L.; Goetz, J.A.; Hutchinson, I.H.; Granetz, R.S.; Greenwald, M.J.; Marmar, E.S.; Mossessian, D.; Porkolab, M.; Taylor, G.; Snipes, J.; Wolfe, S.M.; Wukitch, S.J.

A Study of Molybdenum Influxes and Transport in Alcator C-Mod

2019-04-15T00:27:19Z

A Study of Molybdenum Influxes and Transport in Alcator C-Mod Lipschultz, B.; Bombard, B.; Pappas, D.A.; Rice, J.E.; Smith, D.; Wukitch, S.

Plasma curvature effects on microwave reflectometry fluctuation measurements

2019-04-10T20:49:46Z

Plasma curvature effects on microwave reflectometry fluctuation measurements Lin, Y.; Nazikian, R.; Irby, J.H.; Marmar, E.S.

Two-dimensional full wave simulation of microwave reflectometry on Alcator C-Mod

2019-04-11T03:39:43Z

Two-dimensional full wave simulation of microwave reflectometry on Alcator C-Mod Lin, Y.; Irby, J.H.; Nazikian, R.; Marmar, E.S.; Mazurenko, A.

High resolution visible continuum imaging diagnostic on the Alcator C-Mod tokamak

2019-04-15T00:27:16Z

High resolution visible continuum imaging diagnostic on the Alcator C-Mod tokamak Marmar, E.S.; Boivin, R.L.; Granetz, R.S.; Hughes, J.W.; Lipschultz, B.; Cool, S.; Mossessian, D.; Pitcher, C.S.; Rice, J.E.; Terry, J.L.

Electromagnetic Wall Torques from Magnetically Confined Plasmas

2019-04-15T00:27:17Z

Electromagnetic Wall Torques from Magnetically Confined Plasmas Hutchinson, Ian

n=1 Resistive Modes in Reversed Magnetic Shear Alcator C-Mod Plasmas

2019-04-09T17:10:43Z

n=1 Resistive Modes in Reversed Magnetic Shear Alcator C-Mod Plasmas In, Y.; Ramos, J.J.; Hubbard, A.E.; Hutchinson, I.H.; Porkolab, M.; Snipes, J.; Wolfe, S.; Bondeson, A.

Identification of Mercier instabilities in Alcator C-Mod tokamak

2019-04-15T00:27:18Z

Identification of Mercier instabilities in Alcator C-Mod tokamak In, Y.; Ramos, J.J.; Hastie, R.J.; Catto, P.J.; Hubbard, A.E.; Hutchinson, I.H.; Marmar, E.; Porkolab, M.; Snipes, J.; Wolfe, S.; Taylor, G.; Bondeson, A.

Confinement criterion for a highly bunched beam

2019-04-15T00:27:16Z

Confinement criterion for a highly bunched beam Hess, Mark; Chen, Chiping

Excitation, propagation, and damping of electron Bernstein waves in tokamaks

2019-04-15T00:27:16Z

Excitation, propagation, and damping of electron Bernstein waves in tokamaks Ram, A.K.; Schultz, S.D.

Stimulated Radiation from Spatiotemporally Gyrating Relativistic Electron Beams

2019-04-10T17:53:33Z

Stimulated Radiation from Spatiotemporally Gyrating Relativistic Electron Beams Davies, J.A.; Chen, C.

X-ray Observations of 2l - nl' Transitions and Configuration Interaction Effects from Kr, Mo, Nb and Zr in Near Neonlike Charge States from Tokamak Plasmas

2019-04-09T16:30:41Z

X-ray Observations of 2l - nl' Transitions and Configuration Interaction Effects from Kr, Mo, Nb and Zr in Near Neonlike Charge States from Tokamak Plasmas Rice, J.; Fournier, K.; Goetz, J.; Marmar, E.; Terry, J.

High Resolution Edge Thomson Scattering Measurements on the Alcator C-Mod Tokamak

2019-04-10T17:53:33Z

High Resolution Edge Thomson Scattering Measurements on the Alcator C-Mod Tokamak Hughes, J.W.; Mossessian, D.A.; Hubbard, A.E.; Marmar, E.S.; Johnson, D.; Simon, D.

Observations of Cold, High Density Plasma in the Private Flux Region of the Alcator C-Mod Divertor

2019-04-11T06:03:06Z

Observations of Cold, High Density Plasma in the Private Flux Region of the Alcator C-Mod Divertor Boswell, C.J.; Terry, J.L.; Bombard, B.; Lipschultz, B.; Goetz, J.A.

Impurity Transport Experiments in the Edge Plasma of Alcator C-Mod using Gas Injection Plumes

2019-04-10T07:34:03Z

Impurity Transport Experiments in the Edge Plasma of Alcator C-Mod using Gas Injection Plumes Gangadhara, S.; Bombard, B.

Applications of visible CCD cameras on the Alcator C-Mod tokamak

2019-04-10T17:53:33Z

Applications of visible CCD cameras on the Alcator C-Mod tokamak Boswell, C.J.; Terry, J.L.; Lipschultz, B.; Stillerman, J.

Stack Mountable Microwave Plasma for Sensitive Real Time Calibrated Metals and Particulate Monitoring

2019-04-15T00:27:13Z

Stack Mountable Microwave Plasma for Sensitive Real Time Calibrated Metals and Particulate Monitoring Woskov, Paul; Hadidi, Kamal; Green, Karyn; Thomas, Paul

Molybdenum sources and transport in Alcator C-Mod

2019-04-10T16:41:01Z

Molybdenum sources and transport in Alcator C-Mod Lipschultz, B.; Pappas, D.A.; Bombard, B.; Rice, J.E.; Smith, D.; Wukitch, S.

Cross-field plasma transport and main chamber recycling in diverted plasmas on Alcator C-Mod

2019-04-11T06:03:04Z

Cross-field plasma transport and main chamber recycling in diverted plasmas on Alcator C-Mod Bombard, B.; Umansky, M.V.; Boivin, R.L.; Goetz, J.A.; Hughes, J.; Lipschultz, B.; Mossessian, D.; Pitcher, C.S.; Terry, J.L.

Interchange modes in a Collisional Plasma

2019-04-15T00:27:13Z

Interchange modes in a Collisional Plasma Kesner, J.

WWW interfaces for runtime relational database applications

2019-04-15T00:27:14Z

WWW interfaces for runtime relational database applications Stillerman, Joshua; Fredian, Thomas; Greenwald, Martin

Emissions Reductions Using Hydrogen from Plasmatron Fuel Converters

2019-04-15T00:27:15Z

Emissions Reductions Using Hydrogen from Plasmatron Fuel Converters Bromberg, L.; Cohn, D.R.; Rabinovich, A.; Heywood, J.

The Alcator C-Mod Divertor Bypass

2019-04-10T19:30:23Z

The Alcator C-Mod Divertor Bypass Pitcher, C.S.; Bombard, B.; Danforth, R.; Pina, W.; Silveira, M.; Parkin, B.

Radial Impurity Transport in the H-Mode Transport Barrier Region in Alcator C-Mod

2019-04-10T17:53:32Z

Radial Impurity Transport in the H-Mode Transport Barrier Region in Alcator C-Mod Pedersen, Thomas; Granetz, Robert; Hubbard, Amanda; Hutchinson, Ian; Marmar, Earl; Rice, John; Terry, James

Simultaneous soft x-ray emissivity profile measurements in poloidally separate locations of the Alcator C-Mod edge plasma

2019-04-10T17:53:32Z

Simultaneous soft x-ray emissivity profile measurements in poloidally separate locations of the Alcator C-Mod edge plasma Pedersen, Thomas; Granetz, Robert

Electron beam halo formation in high-power periodic permanent magnet focusing klystron amplifiers

2019-04-15T00:27:15Z

Electron beam halo formation in high-power periodic permanent magnet focusing klystron amplifiers Pakter, R.; Chen, C.

Comparison of Edge Fluctuation Measurements from PCI, BES, Langmuir Probes and Reflectometry on DIII-D

2019-04-11T04:24:28Z

Comparison of Edge Fluctuation Measurements from PCI, BES, Langmuir Probes and Reflectometry on DIII-D Rost, J.C.; Porkolab, M.; Rhodes, T.L.; Moyer, R.A.; Kee, G.R.; Burrell, K.H.

Import Data from File (IDF) utilities for programming data input to scientific codes

2019-04-10T17:53:31Z

Import Data from File (IDF) utilities for programming data input to scientific codes Pigarov, A.; Saltanova, I.V.

H-mode pedestal studies in Alcator C-Mod

2019-04-11T04:24:27Z

H-mode pedestal studies in Alcator C-Mod Mossessian, D.; Hughes, J.; Hubbard, A.; Marmar, E.; Wolfe, S.

Heating and current drive by electron Bernstein waves in NSTX and mast-type plasmas

2019-04-09T16:34:23Z

Heating and current drive by electron Bernstein waves in NSTX and mast-type plasmas Ram, A.K.; Schultz, S.D.; Davies, C.N.; Cairns, R.A.; Efthimion, P.C.; Taylor, G.

Helium-3 Transport Experiments in the Scrape-Off Layer with the Alcator C-Mod Omegatron Ion Mass Spectrometer

2019-04-15T00:27:14Z

Helium-3 Transport Experiments in the Scrape-Off Layer with the Alcator C-Mod Omegatron Ion Mass Spectrometer Nachtrieb, R.; Bombard, B.; Thomas, E.

Mechanisms and Control of Beam Halo Formation in Intense Microwave Sources and Accelerators

2019-04-11T04:24:27Z

Mechanisms and Control of Beam Halo Formation in Intense Microwave Sources and Accelerators Chen, C.; Pakter, R.

Omegatron Ion Mass Spectrometer for the Alcator C-Mod Tokamak

2019-04-15T00:27:14Z

Omegatron Ion Mass Spectrometer for the Alcator C-Mod Tokamak Nachtrieb, R.; Bombard, B.; Thomas, E.

Measurements and Scalings of the H-mode Pedestal on Alcator C-Mod

2019-04-15T00:27:14Z

Measurements and Scalings of the H-mode Pedestal on Alcator C-Mod Mossessian, D.; Hubbard, A.E.; Marmar, E.S.; Pedersen, T.; Granetz, R.S.; Boivin, R.L.; Greenwald, M.; Hughes, J.; Irby, J.; Johnson, D.; Bombard, B.; Lin, Y.; Mazurenko, A.; Nazikian, R.; Pitcher, C.S.; Taylor, G.; Wolfe, S.M.