Precision measurement of the mass and lifetime of the Ξ0b Baryon

Abstract

Using a proton-proton collision data sample corresponding to an integrated luminosity of 3 fb-1 collected by LHCb at center-of-mass energies of 7 and 8 TeV, about 3800 Ξ0b Ξ+cπ-, Ξc+ pK-π+ signal decays are reconstructed. From this sample, the first measurement of the Ξ0b baryon lifetime is made, relative to that of the Λ0b baryon. The mass differences M(Ξ0b) - M(Λ0b) and M(Ξc+) - M(Λc+) are also measured with precision more than 4 times better than the current world averages. The resulting values are (Equation presented) where the first factor is the ratio of fragmentation fractions, b Ξ0b relative to b Λ0b. Relative production rates as functions of transverse momentum and pseudorapidity are also presented.