Lifetime Difference and CP Asymmetry in the Bs -> J/psi phi decay

Abstract

The B{sub s} meson is an interesting particle to study because a sizable mixing induced CP violation in the B{sub s} -- {bar B}{sub s} system would be an indication for physics beyond the Standard Model. In this paper we present a measurement of the lifetime difference {Delta}{Gamma} between the B{sub s} mass eigenstates and the CP violating phase in the decay B{sub s} {yields} J/{psi}{phi}. In 1.7 fb{sup -1} of data collected with the CDF II detector at the Tevatron p{bar p} collider we measure {Delta}{Gamma} = 0.076{sup +0.059}{sub -0.063} (stat.) {+-}0.006 (syst.) ps{sup -1}, well consistent with the Standard Model prediction, and a mean B{sub s} lifetime of c{sub tau}{sub s} = 456 {+-} 13 (stat.) {+-} (syst.) {micro}m. We find no evidence for CP violation.