First study of the CP-violating phase and decay-width difference in Bs0→ψ(2S)ϕ decays

Abstract

A time-dependent angular analysis of B0 s → ψ(2S)φ decays is performed using data recorded by the LHCb experiment. The data set corresponds to an integrated luminosity of 3.0 fb−1 collected during Run 1 of the LHC. The CP-violating phase and decay-width difference of the B0 s system are measured to be φs = 0.23+0.29 −0.28 ± 0.02 rad and s = 0.066+0.041 −0.044 ± 0.007 ps−1, respectively, where the first uncertainty is statistical and the second systematic. This is the first time that φs and s have been measured in a decay containing the ψ(2S) resonance.