Weak Radiative B-Meson Decay Beyond Leading Logarithms

Abstract

We present our results for three-loop anomalous dimensions necessary in analyzing \(B{\to}X_s\gamma\) decay at the next-to-leading order in QCD. We combine them with other recently calculated contributions, obtaining a practically complete next-to-leading order prediction for the branching ratio \({\cal B}(B{\to}X_s\gamma) = (3.28 \pm 0.33) \times 10^{-4}\). The uncertainty is more than twice smaller than in the previously available leading order theoretical result. The Standard Model prediction remains in agreement with the CLEO measurement at the \(2 \sigma\) level.