First observation and branching fraction measurement of the Λb0→Ds−p decay

Abstract

The first observation of the Λ 0 b → D− s p decay is presented using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of √ s = 13 TeV, corresponding to a total integrated luminosity of 6 fb−1 . Using the Λ 0 b → Λ + c π − decay as the normalisation mode, the branching fraction of the Λ 0 b → D− s p decay is measured to be B(Λ 0 b → D− s p) = (12.6 ± 0.5 ± 0.3 ± 1.2) × 10−6 , where the first uncertainty is statistical, the second systematic and the third due to uncertainties in the branching fractions of the Λ 0 b → Λ + c π −, D− s → K−K+π − and Λ + c → pK−π + decays.