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arXiv · 1005.5587

Complete (O_7,O_8) contribution to B -> X_s gamma at order alpha_s^2

H. M. Asatrian·T. Ewerth·A. Ferroglia·C. Greub·G. Ossola
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Abstract

We calculate the set of O(alpha_s^2) corrections to the branching ratio and to the photon energy spectrum of the decay process B -> X_s gamma originating from the interference of diagrams involving the electromagnetic dipole operator O_7 with diagrams involving the chromomagnetic dipole operator O_8. The corrections evaluated here are one of the elements needed to complete the calculations of the B -> X_s gamma branching ratio at next-to-next-to-leading order in QCD. We conclude that this set of corrections does not change the central value of the Standard Model prediction for Br(B -> X_s gamma) by more than 1 %.

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H. M. Asatrian, T. Ewerth, A. Ferroglia, C. Greub, G. Ossola. 2010-05-31. Complete (O_7,O_8) contribution to B -> X_s gamma at order alpha_s^2. https://doi.org/10.1103/physrevd.82.074006

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