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Towards the NNLL precision in $\bar B \to X_s γ$

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

The present NLL prediction for the decay rate of the rare inclusive process $\bar B \to X_s γ$ has a large uncertainty due to the charm mass renormalization scheme ambiguity. We estimate that this uncertainty will be reduced by a factor of 2 at the NNLL level. This is a strong motivation for the on-going NNLL calculation, which will thus significantly increase the sensitivity of the observable $\bar B \to X_s γ$ to possible new degrees of freedom beyond the SM. We also give a brief status report of the NNLL calculation.

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H. Asatrian, A. Hovhannisyan, V. Poghosyan, C. Greub, T. Hurth. 2005-12-08. Towards the NNLL precision in $\bar B \to X_s γ$. https://arxiv.org/abs/hep-ph/0512097

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