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Rare decays $\bar{B}\to X_{s(d)}γ$ at the NLO

H. M. Asatrian·H. H. Asatryan·A. Hovhannisyan
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Abstract

We present an independent calculation of ${\cal{O}}(α_s)$ matrix elements of the QCD penguin operators for the decays $\bar{B}\to X_{s(d)}γ$. The Mellin-Barnes representation technique is applied for the systematic numerical evaluation of involved two-loop diagrams. The numerical effect of the calculated contributions is confirmed to be of order of 1%. We also present an updated numerical analysis for $\bar{B}\to X_{s(d)}γ$ decay rates.

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H. M. Asatrian, H. H. Asatryan, A. Hovhannisyan. 2004-01-28. Rare decays $\bar{B}\to X_{s(d)}γ$ at the NLO. https://doi.org/10.1016/j.physletb.2004.02.013

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