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NNLL QCD Contribution of the Electromagnetic Dipole Operator to Gamma(anti-B -> X(s) gamma)

H. M. Asatrian·A. Hovhannisyan·V. Poghosyan·T. Ewerth·C. Greub·T. Hurth
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Abstract

We present an independent calculation of that part of the O(α_s^2) contribution to the decay width Γ(\bar B -> X_s γ) which arises from the self-interference term of the electromagnetic dipole operator O_7. Using a different method, we find complete agreement with a previous calculation. This NNLL contribution is an important ingredient for the complete NNLL prediction of Γ(\bar B -> X_s γ) which will resolve the charm quark mass ambiguity appearing at NLL accuracy.

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H. M. Asatrian, A. Hovhannisyan, V. Poghosyan, T. Ewerth, C. Greub, T. Hurth. 2006-04-30. NNLL QCD Contribution of the Electromagnetic Dipole Operator to Gamma(anti-B -> X(s) gamma). https://doi.org/10.1016/j.nuclphysb.2006.05.026

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