New physics in rare B decays after Moriond 2021

Abstract

The anomalies in rare B decays endure. We present results of an updated global analysis that takes into account the latest experimental input – in particular the recent results on RK and BR(Bs→ μ+μ-) – and that qualitatively improves the treatment of theory uncertainties. Fit results are presented for the Wilson coefficients of four-fermion contact interactions. We find that muon specific Wilson coefficients C9≃ - 0.73 or C9= - C10≃ - 0.39 continue to give an excellent description of the data. If only theoretically clean observables are considered, muon specific C10≃ 0.60 or C9= - C10≃ - 0.35 improve over the Standard Model by Δχ2≃4.7σ and Δχ2≃4.6σ, respectively. In various new physics scenarios we provide predictions for lepton flavor universality observables and CP asymmetries that can be tested with more data. We update our previous combination of ATLAS, CMS, and LHCb data on BR(Bs→ μ+μ-) and BR(B→ μ+μ-) taking into account the full two-dimensional non-Gaussian experimental likelihoods.