Effects of Anomalous Tensor Couplings in B_s⁰−B_s⁰ 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 φ_s^{J/ψ(φ,f₀)}, a_sl^s and ΔM_s, 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 B_s⁰-B_s⁰ mixing. Numerically, the observable a_sl^s 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 φ_T1=41°±35° or φ_T8=−47°±33° and relevant strength parameters |g_T1|=(2.89±1.40)×10⁻² or |g_T8|=(0.79±0.34)×10⁻². However, due to the fact that the NP contributions are severely suppressed by the recent LHCb measurement for φ_s^{J/ψ(φ,f₀)}, our theoretical result of a_sl^s is still much smaller than the central value of the experimental data.