Constraints on new physics from radiative $B$ decays

Abstract

A new phase for the measurements of radiative decay modes in $b\to s$ transitions has started with new measurements of exclusive modes by LHCb and with Belle-II showing distinctive promises in both inclusive and exclusive channels. After critically reviewing the hadronic uncertainties in exclusive radiative decays, we analyze the impact of recent measurements of the branching ratio and mass-eigenstate rate asymmetry in $B_s\to \varphi \gamma$ and of the angular distribution of $B\to K^{\ast }{e}^{+}{e}^{-}$ at low $q^2$ on new physics in the $b\to s\gamma$ transition.

Comments: 22 pages, 3 figures. v3: Minor numerical updates, references added, one figure added. Conclusions unchanged