331- Z′ mediated FCNC effects on b → d μ < sup > + < /sup > μ < sup > - < /sup > Transitions

Abstract

We study the rare semileptonic B → πμ+μ- and B → pμ+μ- decay modes mediated by the quark level b → dμ+μ- transition in this paper. We analyze observables such as the differential branching ratio, lepton polarization asymmetry and forward-backward asymmetry within the standard model in the large hadronic recoil region. We then analyze these observables within the 331 or SUC(3) × SUL(3) × UX(1) model in which a new heavy Z′ boson contributes. The effects of the Z′-mediated flavor changing neutral current (FCNC) transitions on these modes are examined by varying the mass MZ′ and the model parameter β. The new Z′ couplings are constrained by flavor observables of Bd -Bd mixing. For the obtained parameter space, we observe Z′ sensitivities of our observables of interest and deviations from standard model can range from moderate to large depending on the β value.