Analysis of the semileptonic Bc → D*sµ+µ- decay mode in the effective field theory approach

Abstract

Discrepancies have been noted between experimental measurements and Standard Model predictions for various observables related to the B → (K, K∗, ϕ)ll processes. Recently, the Belle-II Collaboration observed a 2.8σ deviation from Standard Model predictions in the branching ratio of the B → Kνl ν¯l decay mode. In this context, we investigate the exclusive semileptonic Bc → D*sµ+µ- decay mode, mediated by b → s quark level transition, using Effective Field Theory formalism. We perform a global fit to the new parameters using existing experimental data on b → sµ+µ−. We then estimate the branching ratio and other observables such as forward-backward asymmetry, lepton polarisation asymmetry, and the lepton non-universality parameter of the Bc → D(*)sµ+µ- process. Although this process has not yet been detected experimentally, we offer predictions and discuss the observables for Bc → D*sµ+µ- in both the Standard Model and potential new physics scenarios.