Two-Loop Electroweak Heavy-Fermion Corrections to Higgs-Boson Production and Decay
نویسندگان
چکیده
The dominant electroweak corrections to the production cross sections and partial decay widths of a light Standard-Model Higgs boson, with mass MH ≪ 2mt, are due to top-quark loops. By means of a low-energy theorem, we study at the twoloop 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(GμmF ) and O(GμmF ), respectively, where mF represents a generic heavy-fermion mass, with mF ≫ MW ,MH . Except for the Hbb̄ coupling, all results carry over to the case of the top-quark-induced corrections. We discuss possible phenomenological consequences of our results. PACS numbers: 12.15.Lk, 12.38.Bx, 14.80.Bn
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