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arXiv · 1002.1071

QCD Corrections in two-Higgs-doublet extensions of the Standard Model with Minimal Flavor Violation

G. Degrassi·P. Slavich
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Abstract

We present the QCD corrections to R_b and to the Delta B=1 effective Hamiltonian in models with a second Higgs field that couples to the quarks respecting the criterion of Minimal Flavor Violation, thus belonging either to the (1,2)_1/2 or to the (8,2)_1/2 representation of SU(3)xSU(2)xU(1). After the inclusion of the QCD corrections, the prediction for R_b becomes practically insensitive to the choice of renormalization scheme for the top mass, which for the type-I and type-II models translates in a more robust lower bound on tan(beta). The QCD-corrected determinations of Rb and BR(B->Xs gamma) are used to discuss the constraints on the couplings of a (colored) charged Higgs boson to top and bottom quarks.

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G. Degrassi, P. Slavich. 2010-02-04. QCD Corrections in two-Higgs-doublet extensions of the Standard Model with Minimal Flavor Violation. https://doi.org/10.1103/physrevd.81.075001

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