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arXiv · hep-ph/0609232

Estimate of BR(B -> X_s gamma) at O(alpha_s^2)

M. Misiak·H. M. Asatrian·K. Bieri·M. Czakon·A. Czarnecki·T. Ewerth·A. Ferroglia·P. Gambino·M. Gorbahn·C. Greub·U. Haisch·A. Hovhannisyan·T. Hurth·A. Mitov·V. Poghosyan·M. Slusarczyk·M. Steinhauser
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Abstract

Combining our results for various O(alpha_s^2) corrections to the weak radiative B-meson decay, we are able to present the first estimate of the branching ratio at the next-to-next-to-leading order in QCD. We find BR(B -> X_s gamma) = (3.15 +_ 0.23) x 10^-4 for E_gamma > 1.6 GeV in the B-meson rest frame. The four types of uncertainties: non-perturbative (5%), parametric (3%), higher-order (3%) and m_c-interpolation ambiguity (3%) have been added in quadrature to obtain the total error.

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M. Misiak, H. M. Asatrian, K. Bieri, M. Czakon, A. Czarnecki, T. Ewerth, A. Ferroglia, P. Gambino, M. Gorbahn, C. Greub, U. Haisch, A. Hovhannisyan, T. Hurth, A. Mitov, V. Poghosyan, M. Slusarczyk, M. Steinhauser. 2006-12-31. Estimate of BR(B -> X_s gamma) at O(alpha_s^2). https://doi.org/10.1103/physrevlett.98.022002

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