Weak-annihilation rare radiative decays of B-mesons

TL;DR

This paper predicts rare radiative B-meson decay rates via weak-annihilation, considering photon emission from both B-meson and vector-meson loops, with estimated branching ratios around 10^-7.

Contribution

It provides new theoretical predictions for B-meson radiative decay branching ratios using the factorization approximation and including photon emission from multiple loops.

Findings

Branching ratio for _s^0  J/ =1.5 7 10^{-7}

Branching ratio for B^-  _s^{*-}  =1.7 7 10^{-7}

Estimated prediction accuracy is about 20%

Abstract

In this talk, we present the predictions for a number of radiative decays $B_{(s)}\to V\gamma$, with the vector meson in the final state, which proceed through the weak-annihilation mechanism. Within the factorization approximation, we take into account the photon emission from the $B$-meson loop and from the vector-meson loop. The highest branching ratios for the weak-annihilation reactions reported here are ${\cal B}(\bar B^0_s\to J/\psi\gamma)=1.5\cdot 10^{-7}$ and ${\cal B}(B^-\to \bar D_s^{*-}\gamma)=1.7\cdot 10^{-7}$, the estimated accuracy of these predictions being at the level of 20%.