Observation of B+ -> K+ eta gamma

TL;DR

This paper reports the first observation of the radiative decay B+ -> K+ eta gamma and evidence for B0 -> K0 eta gamma, providing new measurements of these rare B meson decay modes.

Contribution

It presents the first observation of B+ -> K+ eta gamma decay and evidence for B0 -> K0 eta gamma, expanding knowledge of radiative B meson decays.

Findings

First observation of B+ -> K+ eta gamma with branching fraction (8.4 +- 1.5(stat) +1.2 -0.9(syst)) x 10^{-6}

Evidence for B0 -> K0 eta gamma decay

Search conducted for B -> K3*(1780) gamma

Abstract

We report measurements of radiative B decays with K eta gamma final states, using a data sample of 253 /fb recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- storage ring. We observe B+ -> K+ eta gamma for the first time with a branching fraction of (8.4 +- 1.5(stat) +1.2 -0.9(syst)) X 10^{-6} for M(Keta) < 2.4 GeV/c^2, and find evidence of B0 -> K0 eta gamma. We also search for B -> K3*(1780) gamma.