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Two-loop QCD corrections to charged-Higgs-mediated $b\to sγ$ decay

P. Ciafaloni·A. Romanino·A. Strumia
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Abstract

The charged-Higgs-mediated contribution to the Wilson coefficient of the $b\to sγ$ magnetic penguin is expected to be one of the more promising candidates for a supersymmetric effect in B physics, probably the only one in gauge-mediated models. We compute the two-loop QCD correction to it. With naive dimensional regularization and MSbar subtraction, for reasonable values of the charged Higgs mass and for mu-bar = m_top, we find a (10--20)% reduction of the corresponding one-loop effect.

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P. Ciafaloni, A. Romanino, A. Strumia. 1997-10-20. Two-loop QCD corrections to charged-Higgs-mediated $b\to sγ$ decay. https://doi.org/10.1016/s0550-3213(98)00190-4

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