Inclusive photon energy spectrum in B decays

Abstract

Inclusive photon energy spectrum and decay rate for the rare radiative decays of theB hadrons,B → γ+X s (hereX s denotes hadrons with total strangeness quantum numberS=−1), are calculated in the standard theory of electroweak interactions, using theb quark decay model. The calculations have been done in the framework of an effective low-energy Lagrangian based on the gauge invariant operators of dimension 6. The large QCD effects, contained in the Wilson coefficients of these operators, are included in our approach. The shape of the photon energy spectrum and the branching ratio BR (B→γ+X s ) are sensitive to the top quark mass.