Measurement of the branching fraction of the $B^{0}rightarrow D_{s}^{+}pi^{-}$ decay

A branching fraction measurement of the $B^{0}rightarrow D_{s}^{+}pi^{-}$ decay is presented using proton-proton collision data collected with the LHCb experiment, corresponding to an integrated luminosity of $5.0,$fb$^{-1}$. The branching fraction is found to be ${mathcal{B}(B^{0}rightarrow D_{s}^{+}pi^{-}) = (19.4 pm 1.8pm 1.3 pm 1.2)times 10^{-6}}$, where the first uncertainty is statistical, the second systematic and the third is due to the uncertainty on the $B^0 to D^{-}pi^{+}$, $D_{s}^{+}rightarrow K^{+}K^{-}pi^{+}$ and $D^{-}rightarrow K^{+}pi^{-}pi^{-}$ branching fractions. This is the most precise single measurement of this quantity to date. As this decay proceeds through a single amplitude involving a $b to u$ charged-current transition, the result provides information on non-factorisable strong interaction effects and the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element $V_{ub}$. Additionally, the collision energy dependence of the hadronisation-fraction ratio $f_s/f_d$ is measured through $bar{B}{}_{s}^{0}rightarrow D_{s}^{+}pi^{-}$ and $B^0 to D^{-}pi^{+}$ decays.