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arXiv · hep-ph/9507213

QCD corrections to charged Higgs-mediated $b \to c τν$ decay

Yuval Grossman·Howard E. Haber·Yosef Nir
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Abstract

We calculate the $O(α_s)$ corrections to the charged Higgs mediated inclusive semi-tauonic $B$ decay. By working in the Landau gauge, we demonstrate how to obtain the charged Higgs contributions (both direct and interference terms) from the known QCD corrections to $t \to b H^+$. Combining our results with $O(1/m_b^2)$ corrections to the spectator model and comparing the theoretical prediction with the recent experimental measurements, we find a model-independent $2σ$ upper bound on the ratio of Higgs vacuum expectation values, $\tanβ<0.52(m_H/1 GeV)$.

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Yuval Grossman, Howard E. Haber, Yosef Nir. 1995-07-03. QCD corrections to charged Higgs-mediated $b \to c τν$ decay. https://doi.org/10.1016/0370-2693(95)00946-i

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