| Abstract |
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We present a measurement of the branching fraction and photon energy
spectrum for the decay B --> Xs gamma using data from the BaBar
experiment. The data sample corresponds to an integrated luminosity
of 210 fb-1, from which approximately 680\,000 BB events are tagged
by a fully reconstructed hadronic decay of one of the B mesons. In
the decay of the second B meson, an isolated high--energy photon is
identified. We measure BF(B -> Xs gamma) = (3.66 +- 0.85_{stat}
+- 0.60_{syst}) x 10^{-4}$ for photon energies E_gamma above 1.9 GeV
in the B rest frame. From the measured spectrum we calculate the first
and second moments for different minimum photon energies, which are
used to extract the heavy-quark parameters m_b and \mu_{\pi}^2. In
addition, measurements of the direct CP asymmetry and isospin
asymmetry are presented.
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