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arXiv · hep-ph/9712330

Two-Loop Electroweak Heavy-Fermion Corrections to Higgs-Boson Production and Decay

Abstract

The dominant electroweak corrections to the production cross sections and partial decay widths of a light Standard-Model Higgs boson, with mass M_H << 2m_t, are due to top-quark loops. By means of a low-energy theorem, we study at the two-loop level the leading shifts in the Higgs-boson couplings to pairs of light fermions and gauge bosons induced by a sequential isodoublet of high-mass fermions. For tree-level and loop-induced Higgs-boson couplings, these corrections are of relative orders O(G_mu^2 m_F^4) and O(G_mu m_F^2), respectively, where m_F represents a generic heavy-fermion mass, with m_F >> M_W, M_H. Except for the Hbb-bar coupling, all results carry over to the case of the top-quark-induced corrections. We discuss possible phenomenological consequences of our results.

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BibTeXRIS

A. Djouadi, P. Gambino, B. A. Kniehl. 1997-12-10. Two-Loop Electroweak Heavy-Fermion Corrections to Higgs-Boson Production and Decay. https://doi.org/10.1016/s0550-3213(98)00147-3

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