文摘
This paper reports the first measurement of the effective 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 of m>ppm> collisions, recorded by the LHCb experiment in 2011 at a centre-of-mass energy of 7 TeV. The results are: and . For the latter measurement, the uncertainty includes both statistical and systematic sources.