An empirical model to determine the hadronic resonance contributions to $\overline{B}{}^0 \to \overline{K}{} ^{*0} \mu ^+ \mu^-$ transitions

Abstract

A method for analysing the hadronic resonance contributions in B¯0→K¯∗0μ+μ− decays is presented. This method uses an empirical model that relies on measurements of the branching fractions and polarisation amplitudes of final states involving JPC=1−− resonances, relative to the short-distance component, across the full dimuon mass spectrum of B¯0→K¯∗0μ+μ− transitions. The model is in good agreement with existing calculations of hadronic non-local effects. The effect of this contribution to the angular observables is presented and it is demonstrated how the narrow resonances in the q2 spectrum provide a dramatic enhancement to CP-violating effects in the short-distance amplitude. Finally, a study of the hadronic resonance effects on lepton universality ratios, RK(∗), in the presence of new physics is presented.