Measurement of the branching fractions of the decays D+ → K−K+K+, D+ → π−π+K+ and D s + → π−K+K+

Abstract

Abstract

The branching fractions of the doubly Cabibbo-suppressed decays D+ → K−K+K+, D+ → π−π+K+ and D

s + → π−K+K+ are measured using the decays D+ → K−π+π+ and D

s + → K−K+π+ as normalisation channels. The measurements are performed using proton-proton collision data collected with the LHCb detector at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 2.0 fb−1. The results are

ℬ

D +

→

K −

K +

K +

ℬ

D +

→

K −

π +

π +

=

6.541 ± 0.025 ± 0.042

×

10

− 4

,

ℬ

D +

→

π −

π +

K +

ℬ

D +

→

K −

π +

π +

=

5.231 ± 0.009 ± 0.023

×

10

− 3

,

ℬ

D s +

→

π −

K +

K +

ℬ

D s +

→

K −

K +

π +

,

=

2.372 ± 0.024 ± 0.025

×

10

− 3

,

$$ \begin{array}{c}\hfill \frac{\mathrm{\mathcal{B}}\left({D}^{+}\to {K}^{-}{K}^{+}{K}^{+}\right)}{\mathrm{\mathcal{B}}\left({D}^{+}\to {K}^{-}{\pi}^{+}{\pi}^{+}\right)} = \left(6.541\pm 0.025\pm 0.042\right)\times {10}^{-4},\hfill \\ {}\hfill \frac{\mathrm{\mathcal{B}}\left({D}^{+}\to\ {\pi}^{-}{\pi}^{+}{K}^{+}\right)}{\mathrm{\mathcal{B}}\left({D}^{+}\to {K}^{-}{\pi}^{+}{\pi}^{+}\right)}=\left(5.231\pm 0.009\pm 0.023\right)\times {10}^{-3},\hfill \\ {}\hfill \frac{\mathrm{\mathcal{B}}\left({D}_s^{+}\to\ {\pi}^{-}{K}^{+}{K}^{+}\right)}{\mathrm{\mathcal{B}}\left({D}_s^{+}\to {K}^{-}{K}^{+}{\pi}^{+}\right), } = \left(2.372\pm 0.024\pm 0.025\right)\times {10}^{-3},\hfill \end{array} $$

where the uncertainties are statistical and systematic, respectively. These are the most precise measurements up to date.