Effective lifetime measurements in the B⁰_s→K⁺K^-, B⁰→K⁺π^-and B⁰_s→π⁺K^-decays

Measurements of the effective lifetimes in the B⁰_s→K⁺K^-, B⁰→ K⁺π^- and B⁰_s→π⁺K^- decays are presented using 1.0 fb^-1 of pp collision data collected at a centre-of-mass energy of 7 TeV by the LHCb experiment. The analysis uses a data-driven approach to correct for the decay time acceptance. The measured effective lifetimes are τB⁰_s→K⁺K^- = 1.407±0.016(stat)±0.007(syst) ps, τB⁰→K⁺π^- = 1.524±0.011(stat)±0.004(syst) ps, τB⁰_s→π⁺K^- = 1.60±0.06(stat)±0.01(syst) ps. This is the most precise determination to date of the effective lifetime in the B⁰_s→K⁺K^- decay and provides constraints on contributions from physics beyond the Standard Model to the B⁰_s mixing phase and the width difference ΔΓ_s.