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arXiv · hep-ph/9608449

Towards a next-to-leading logarithmic result in $B \to X_s γ$

Christoph Greub·Tobias Hurth
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Abstract

The calculation of the $O(\a_s)$ virtual corrections to the matrix element of the inclusive decay $b \to s γ$ is reported. These contributions drastically reduce the large renormalization scale dependence of the leading logarithmic calculation. Combining these results with the preliminary result for the Wilson coefficient $C_7(m_b)$ calculated recently by Chetyrkin, Misiak, and Münz, we estimate the branching ratio to be $BR(B \to X_s γ)=(3.25 \pm 0.50) \times 10^{-4}$.

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Christoph Greub, Tobias Hurth. 1996-08-27. Towards a next-to-leading logarithmic result in $B \to X_s γ$. https://arxiv.org/abs/hep-ph/9608449

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