An exploration of Bs→J/ψss¯

摘要

Measurements of the $B_s^0$--$ar{B}_s^0$ mixing phase $phi_s$ appear to beconverging towards the SM prediction, suggesting that contributions from NewPhysics (NP), if present, are small. This poses the question of whethersmallish NP in $phi_s$ can be distinguished from the hadronic uncertaintiespresent in the interfering $B_s$ decay mode. In this paper we discuss thepotential of extracting $phi_s$ from the decay modes $B_so J/psieta^{(prime)}$ and $B_so J/psi f_0(980)$ and how their respective hadronicuncertainties can be controlled. In addition, we demonstrate how the branchingratios of the former decays can be used to estimate the $eta$--$eta'$ mixingangles. Finally, we point out that effective lifetime measurements of decaymodes such as the $B_so J/psi f_0(980)$ can be used to constrain both$phi_s$ and the $B_s$ decay width difference $DeltaGamma_s$, complementaryto the usual time-dependent tagged analysis.