Measurement of B-->K*gamma Branching Fractions and Charge Asymmetries

Abstract

The branching fractions of the exclusive decays $B^0\to K^{\ast 0}\gamma$ and $B^{+}\to K^{\ast +}\gamma$ are measured from a sample of $(22.74\pm 0.36)\times 10^6$ $B\bar{B}$ decays collected with the BABAR detector at the PEP II asymmetric $e^{+}{e}^{-}$ collider. We find $\mathcal{B}(B^0\to K^{\ast 0}\gamma )=(4.23\pm 0.40(stat.)\pm 0.22(sys.))\times 10^{-5}$, $\mathcal{B}(B^{+}\to K^{\ast +}\gamma )=(3.83\pm 0.62(stat.)\pm 0.22(sys.))\times 10^{-5}$ and constrain the CP-violating charge asymmetry to be $-0.170<A_{CP}(B\to K^{\ast }\gamma )<0.082$ at 90% C.L.

7 pages, 3 figures, submitted to Physical Review Letters