NNLO QCD counterterm contributions to $B$ \to $X_s \gamma$ for the physical value of $m_c$

Mikolaj Misiak; Abdur Rehman; Matthias Steinhauser

doi:10.1016/j.physletb.2017.05.008

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arXiv · 1702.07674

NNLO QCD counterterm contributions to $B$ \to $X_s \gamma$ for the physical value of $m_c$

Mikolaj Misiak·Abdur Rehman·Matthias Steinhauser

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Abstract

One of the most important O($\alpha_s^2$) corrections to the $B \to X_s \gamma$ branching ratio originates from interference of contributions from the current-current and photonic dipole operators. Its value has been estimated using an interpolation in the charm quark mass between the known results at $m_c=0$ and for $m_c \ll m_b/2$. An explicit calculation for the physical value of $m_c$ is necessary to remove the associated uncertainty. In the present work, we evaluate all the ultraviolet counterterm contributions that are relevant for this purpose.

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Mikolaj Misiak, Abdur Rehman, Matthias Steinhauser. 2017-02-24. NNLO QCD counterterm contributions to $B$ \to $X_s \gamma$ for the physical value of $m_c$. https://doi.org/10.1016/j.physletb.2017.05.008

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