Effective lifetime measurements in the B[0 over s]--> K+K−, B[superscript 0]-->K+π− and B[0 over s]-->π+K− decays

Abstract

Measurements of the effective lifetimes in the B[0 over s]→K+K−, B0→K+π−B[superscript 0]→K+π− and B[0 over s]→π+K− decays are presented using 1.0 fb−11.0 fb[superscript −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.