PT Journal AU LHCb Collaboration (Aaij, Rea Henry, L Jashal, BK Martinez-Vidal, F Oyanguren, A Remon Alepuz, C Ruiz Vidal, J TI Measurement of the branching fraction of the B0 -> Ds+ pi- decay SO European Physical Journal C JI Eur. Phys. J. C PY 2021 BP 314 - 15pp VL 81 IS 4 DI 10.1140/epjc/s10052-020-08790-2 LA English AB A branching fraction measurement of the B0 -> Ds+pi- decay is presented using proton-proton collision data collected with the LHCb experiment, corresponding to an integrated luminosity of 5.0fb-1. The branching fraction is found to be B(B0 -> Ds+pi-)=(19.4 +/- 1.8 +/- 1.3 +/- 1.2)x10-6, where the first uncertainty is statistical, the second systematic and the third is due to the uncertainty on the B0 -> D-pi+, Ds+-> K+K-pi+ and D--> 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 -> u charged-current transition, the result provides information on non-factorisable strong interaction effects and the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element Vub. Additionally, the collision energy dependence of the hadronisation-fraction ratio fs/fd is measured through Bs0 -> Ds+pi- and B0 -> D-pi + decays. ER