Search for the Radiative Decays B -> rho gamma and B0 -> omega gamma

TL;DR

This paper reports a search for specific rare radiative B meson decays, finding no significant signals and setting upper limits on their branching fractions, thereby constraining theoretical models of these processes.

Contribution

The study provides the first upper limits on the branching fractions of B -> rho gamma and B0 -> omega gamma decays using a large data sample from BaBar, improving constraints on these rare decays.

Findings

No significant signals observed in the decay channels.

Upper limits set on branching fractions at 90% confidence level.

Combined limit on B -> rho gamma branching fraction is 1.9 x 10^-6.

Abstract

A search for the exclusive radiative decays B --> rho(770) gamma and B0 --> omega(782) gamma is performed on a sample of about 84\times 10^{6} B\bar B events collected by the BaBar detector at the PEP-II asymmetric-energy e+e- storage ring. No significant signal is seen in any of the channels. We set upper limits on the branching fractions of BR(B^0 -> rho^0 gamma) < 1.2 \times 10^{-6}, BR(B^+ -> rho^+ gamma) < 2.1 \times 10^{-6}, and BR(B^0 -> omega gamma) < 1.0 \times 10^{-6} at 90% confidence level (C.L.). Using the assumption that Gamma(B --> rho gamma) = Gamma(B+ --> rho+ gamma) =2\times\Gamma(B0 --> rho0 gamma), we find the combined limit BR(B --> rho gamma)<1.9 \times 10^{-6}, corresponding to BR(B --> rho gamma)/\BR(B --> K* gamma) < 0.047 at 90% C.L.