Non-universal $$Z'$$ Boson Effects in Rare Radiative Decay $$ B_s^0\rightarrow \mu ^+ \mu ^-\gamma $$

Abstract

The rare radiative leptonic decay \( B_s^0\rightarrow l^+ l^-\gamma \) is one of the important sectors that accommodates the possibilities of physics beyond the standard model (SM). In this paper, we estimate the branching ratio for the \( B_s^0\rightarrow \mu ^+ \mu ^-\gamma \) decay in a family non-universal \(Z'\) model which can be derived from the extension of SM by including an additional \( U' (1) \) gauge symmetry to the SM symmetry. We find the branching ratio of \( B_s^0\rightarrow \mu ^+ \mu ^-\gamma \) decay depends severely on coupling of \(Z'\) boson with leptons and quarks.