Effective lifetime measurements in theBs0→K+K−,B0→K+π−andBs0→π+K−decays

Measurements of the effective lifetimes in the Bs0→K+K−, B0→K+π− and Bs0→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 τBs0→K+K−=1.407±0.016(stat)±0.007(syst) ps, τB0→K+π−=1.524±0.011(stat)±0.004(syst) ps, τBs0→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 Bs0→K+K− decay and provides constraints on contributions from physics beyond the Standard Model to the Bs0 mixing phase and the width difference ΔΓs.