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arXiv · 2006.00624

Resolved $1/m_b$ contributions to $\bar B \to X_{s,d} \ell^+\ell^-$ and $\bar B \to X_s \gamma$

Michael Benzke·Tobias Hurth
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Abstract

In view of the importance of the nonperturbative resolved contributions for the overall uncertainties of the two inclusive penguin decays $\bar B \to X_s \gamma$ and $\bar B \to X_{s,d} \ell^+\ell^-$ we reanalyse these contributions using new estimates of moments of the subleading shape functions and of other input parameters. Within a systematic approach we find a significant reduction of the nonperturbative uncertainties in the inclusive decay $\bar B \to X_{s,d} \ell^+\ell^-$, but a much less pronounced reduction in the inclusive decay $\bar B \to X_s \gamma$ compared to a recent analysis on the resolved contributions to the inclusive decay $\bar B \to X_s \gamma$. We identify the reasons for this discrepancy.

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Michael Benzke, Tobias Hurth. 2020-05-31. Resolved $1/m_b$ contributions to $\bar B \to X_{s,d} \ell^+\ell^-$ and $\bar B \to X_s \gamma$. https://doi.org/10.1103/physrevd.102.114024

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