Virtual corrections to the decay $b\to s\gamma$

Abstract

We calculate the $O({\text{a}}_s)$ virtual corrections to the matrix element for $b\to s\gamma$, taking into account the contributions of the four-Fermi operator $O_2$ and the electromagnetic and color dipole-type operators. The results are combined with existing $O({\text{a}}_s)$ Bremsstrahlung corrections in order to obtain the relevant inclusive rate. The new result drastically reduces the large scale dependence of the leading logarithmic approximation. It implies that a very accurate prediction for the branching ratio for $B\to X_s\text{g}$ will become possible once also the corrections to the Wilson coefficients are available.

Comments: 11 pages and 4 postscript figures, uses epsfig.sty