Reduction of Charm Quark Mass Scheme Dependence in $\bar B \to X_s γ$ at the NNLL Level

H. M. Asatrian; C. Greub; A. Hovhannisyan; T. Hurth; V. Poghosyan

doi:10.1016/j.physletb.2005.05.080

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Reduction of Charm Quark Mass Scheme Dependence in $\bar B \to X_s γ$ at the NNLL Level

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

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Abstract

The uncertainty of the theoretical prediction of the $\bar B \to X_s γ$ branching ratio at NLL level is dominated by the charm mass renormalization scheme ambiguity. In this paper we calculate those NNLL terms which are related to the renormalization of $m_c$, in order to get an estimate of the corresponding uncertainty at the NNLL level. We find that these terms significantly reduce (by typically a factor of two) the error on ${BR}(\bar B \to X_s γ)$ induced by the definition of $m_c$. Taking into account the experimental accuracy of around 10% and the future prospects of the $B$ factories, we conclude that a NNLL calculation would increase the sensitivity of the observable $\bar B \to X_s γ$ to possible new degrees of freedom beyond the SM significantly.

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H. M. Asatrian, C. Greub, A. Hovhannisyan, T. Hurth, V. Poghosyan. 2005-06-14. Reduction of Charm Quark Mass Scheme Dependence in $\bar B \to X_s γ$ at the NNLL Level. https://doi.org/10.1016/j.physletb.2005.05.080

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