Observation of Ξb0→Ξc+Ds- and Ξb-→Ξc0Ds- decays

Abstract

The Ξb0→Ξc+Ds- and Ξb-→Ξc0Ds- decays are observed for the first time using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of s=13TeV, corresponding to an integrated luminosity of 5.1fb-1. The branching fractions times the production cross-sections of Ξb baryons relative to that of Λb0 baryon are measured to be (Formula presented.) where the first uncertainties are statistical, the second systematic, and the third due to the uncertainties on the decay branching fractions of relevant charmed baryons. The masses of Ξb0 and Ξb- baryons are measured to be mΞb0=5791.12±0.60±0.45±0.24MeV/c2 and mΞb-=5797.02±0.63±0.49±0.29MeV/c2, where the uncertainties are statistical, systematic, and those due to charmed-hadron masses, respectively.