A PROFILE OF THE FINAL-STATES IN B-]XS+GAMMA AND AN ESTIMATE OF THE BRANCHING RATIO BR(B-]K-STAR+GAMMA)

We present an estimate of the inclusive photon energy- and hadron mass-spectrum in rare B decays B --> X(s) + gamma, based on perturbative QCD and a phenomenological model for the B-meson wave function (here X(s) denotes hadrons with total strangeness quantum number S = -1). The shapes of the spectra are sensitive to the details of the wave function and the top quark mass, m(t), but the normalization is essentially determined by m(t). We find BR (B --> X(s) + gamma) = (3-4) X 10(-4) for 100 less-than-or-equal-to m(t) less-than-or-equal-to 200 GeV. With the additional assumption that the K* resonance saturates the recoil hadron mass spectrum in the interval (M(K) + M-pi) less-than-or-equal-to m(X)s less-than-or-equal-to 1 GeV, we calculate the branching ratio BR (B --> K* + gamma) and predict BR (B --> K* + gamma) = (5(-2)+3) X 10(-5), where the errors reflect the uncertainties on the hadronic wave function and the top quark mass in the stated range.