Measurement of the branching fraction and photon energy moments of B -Xsγ and ACP(B → Xs+dγ)

The photon spectrum in B→Xsγ decay, where Xs is any strange hadronic state, is studied using a data sample of 88.5×106 e+e-→Υ(4S)→BB decays collected by the BABAR experiment at the Stanford Linear Accelerator Center. The partial branching fraction, ΔB(B→Xsγ)=(3.67±0.29(stat)±0.34(syst)±0. 29(model))×10-4, the first moment Eγ=2.288±0.025±0. 017±0.015GeV, and the second moment Eγ2=0.0328±0. 0040±0.0023±0.0036GeV2 are measured for the photon energy range 1.9GeV 1.6GeV. In addition, the direct CP asymmetry ACP(B→Xs+dγ) is measured to be -0.110±0.115(stat) ±0.017(syst). © 2006 The American Physical Society.