Measurement of CP violation in $B_{s}^{0}→ϕϕ$ decays

Abstract

A measurement of the decay time dependent $CP$-violating asymmetry in $B_{s}^{0} →ϕϕ$ decays is presented, along with measurements of the $T$-odd triple-product asymmetries. In this decay channel, the CP-violating weak phase arises from the interference between $B_{s}^{0}-\bar B_{s}^{0}$ mixing and the loop-induced decay amplitude. Using a sample of proton-proton collision data corresponding to an integrated luminosity of $3.0fb^{−1}$ collected with the LHCb detector, a signal yield of approximately 4000 $B_{s}^{0}→ϕϕ$ decays is obtained. The $CP$-violating phase is measured to be $ϕ_{s}=−0.17±0.15(stat)±0.03(syst) rad$. The triple-product asymmetries are measured to be $A_{U}=−0.003±0.017(stat)±0.006(syst)$ and $A_{V}=−0.017±0.017(stat)±0.006(syst)$. Results are consistent with the hypothesis of $CP$ conservation.