We give a more complete calculation of b→sγ decay, including leading log QCD corrections from ${\mathit{m}}_{\mathit{t}}$ to ${\mathit{M}}_{\mathit{W}}$ in addition to corrections from ${\mathit{M}}_{\mathit{W}}$ to ${\mathit{m}}_{\mathit{b}}$. We have included the full set of dimension-6 operators and corrected numerical mistakes of anomalous dimensions in a previous paper. Compared with the calculations without QCD running from ${\mathit{m}}_{\mathit{t}}$ to ${\mathit{M}}_{\mathit{W}}$, the inclusive decay rate is found to be enhanced. At ${\mathit{m}}_{\mathit{t}}$=150 GeV, it results in a 12% enhancement, and for ${\mathit{m}}_{\mathit{t}}$=250 GeV, 15% is found. The total QCD effect makes an enhanced factor of 4.2 at ${\mathit{m}}_{\mathit{t}}$=150 GeV, and 3.2 for ${\mathit{m}}_{\mathit{t}}$=250 Gev.

• Received 12 October 1993

DOI:https://doi.org/10.1103/PhysRevD.52.3978