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arXiv · hep-ph/9602281

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

C. Greub·T. Hurth·D. Wyler
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Abstract

We calculate the $O(\a_s)$ virtual corrections to the matrix element for $b \to s γ$, 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 $O(\a_s)$ 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 \g $ will become possible once also the corrections to the Wilson coefficients are available.

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C. Greub, T. Hurth, D. Wyler. 1996-02-13. Virtual corrections to the decay $b \to s γ$. https://doi.org/10.1016/0370-2693(96)00496-0

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