Measurement of the B0 and Bs0 lifetimes in the decay modes B0 → J/ψK∗0 and Bs0 → J/ψφ in ATLAS

The lifetimes of B0 and B0 mesons are determined from their decays Bd0 → J/ψK∗0 and Bs0 →J/ψφ reconstructed in ATLAS using the pp collisions data at acenter-of-mass energy of 7 TeV corresponding to an integrated luminosity of 40 pb−1. For Bd0 meson the lifetime extracted from fit is τBd =1.51 ± 0.04 (stat) ± 0.04 (syst) ps. For the Bs meson the fitted (single) lifetime is τBs single =1.41 ± 0.08 (stat) ± 0.04 (syst) ps. Within the uncertainties, the fitted lifetimes of both B mesons are consistent with the world average values.