Observation of charmless baryonic decays B(s) 0→p p ¯h+h'-

Abstract

Decays of B0 and Bs0 mesons to the charmless baryonic final states p p ¯h+h'-, where h and h' each denote a kaon or a pion, are searched for using the LHCb detector. The analysis is based on a sample of proton-proton collision data collected at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb-1 . Four-body charmless baryonic Bs0 decays are observed for the first time. The decays Bs0→p p ¯K+K-, Bs0→p p ¯K±π∓, B0→p p ¯K±π∓ and B0→p p ¯π+π- are observed with a significance greater than 5 standard deviations; evidence at 4.1 standard deviations is found for the B0→p p ¯K+K- decay and an upper limit is set on the branching fraction for Bs0→p p ¯π+π-. Branching fractions in the kinematic region m (p p ¯ )<2850 MeV /c2 are measured relative to the B0→J /ψ (→p p ¯)K*(892 )0 channel.