Effects of Anomalous Tensor Couplings in B 0 s — B̄ 0 s Mixing

Motivated by the recently observed anomalous large dimuon charge asymmetry in neutral B decays, we study the effects of the anomalous tensor couplings to pursue a possible solution. With the constraints from the observables sJ/ψ(,f0), assl and ΔMs, the new physics parameter spaces are severely restricted. We find that the contributions induced by the color-singlet or the color-octet tensor operators are helpful to moderate the anomaly in B0s — 0s mixing. Numerically, the observable assl could be enhanced by about two orders of magnitude by the contributions of color-singlet or color-octet tensor operators with their respective nontrivial new weak phase T1 = 41° ± 35° or T8 = −47° ± 33° and relevant strength parameters |gT1| = (2.89 ± 1.40) × 10−2 or |gT8| = (0.79 ± 0.34) × 10−2. However, due to the fact that the NP contributions are severely suppressed by the recent LHCb measurement for sJ/ψ(,f0), our theoretical result of assl is still much smaller than the central value of the experimental data.