This paper reports the first measurement of the effective B 0 s →J/ψK 0 S lifetime and an updated measurement of its time-integrated branching fraction. Both measurements are performed with a data sample, corresponding to an integrated luminosity of 1.0 fb -1 of pp collisions, recorded by the LHCb experiment in 2011 at a centre-of-mass energy of 7 TeV. The results are: τ eff J/ψK 0S = 1.75±0.12 (stat)±0.07 (syst) ps and B(B 0 S →J/ψK 0 S) = (1.97 ± 0.23) × 10 -5. For the latter measurement, the uncertainty includes both statistical and systematic sources.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics