On the effective lifetime of Bs → μμγ

A bstract We consider the $$ {B}_s^0 B s 0 → μ + − γ effective lifetime, and related CP-phase sensitive quantity {A}_{{\Delta \Gamma}_s}^{\mu \mu \gamma} A ΔΓ μμγ , as a way to obtain qualitatively new insights on current B -decay discrepancies. Through fit comparing pre- post-Moriond-2021 data we identify few theory benchmark scenarios addressing these discrepancies, featuring large CP violation in addition. then explore possibility of telling apart with once resonance-modeling form-factor uncertainties are taken into account. do so both regions low high invariant di-lepton mass-squared q 2 . For show how shape integration range order reduce impact ϕ -resonance modelling prediction. find that corresponding pollution from broad-charmonium resonances has surprisingly small effect This is due number cancellations, can be traced back complete dominance semi-leptonic operator contributions for — at variance behaving like ratio-of-amplitudes observable. Our study suggests especially potentially valuable probe short-distance CP-violating effects very same Wilson coefficients associated b s Its discriminating power, however, relies progress uncertainties. Interestingly, region where already being accessed experimentally, form factors more accessible through non-perturbative QCD methods.