Measurement of B→K∗(892)γ branching fractions and CP and isospin asymmetry

Abstract

We present an analysis of the decays B0→K*0(892)γ and B+→K*+(892)γ using a sample of about 383×106 B¯¯¯B events collected with the BABAR detector at the PEP-II symmetric energy B factory. We measure the branching fractions B(B0→K*0γ)=(4.47±0.10±0.16)×1− 5 and B (B+→K*+γ)=(4.22±0.14±0.16)×10−5. We constrain the direct CP asymmetry to be −0.033<A(B→K∗γ)<0.028 and the isospin asymmetry to be 0.017<Δ0−<0.116, where the limits are determined by the 90% confidence interval and include both the statistical and systematic uncertainties.