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Virtual Top-Quark Effects on the H->bb-bar Decay at Next-to-Leading Order in QCD

K. G. Chetyrkin·B. A. Kniehl·M. Steinhauser
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Abstract

By means of a heavy-top-quark effective Lagrangian, we calculate the three-loop corrections of O(alpha_s^2 G_F M_t^2) to the H->bb-bar partial decay width of the standard-model Higgs boson with intermediate mass M_H<<2M_t. We take advantage of a soft-Higgs theorem to construct the relevant coefficient functions. We present our result both in the MS-bar and on-shell schemes of mass renormalization. The MS-bar formulation turns out to be favourable with regard to the convergence behaviour. We also test a recent idea concerning the naive non-abelianization of QCD.

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K. G. Chetyrkin, B. A. Kniehl, M. Steinhauser. 1996-10-23. Virtual Top-Quark Effects on the H->bb-bar Decay at Next-to-Leading Order in QCD. https://doi.org/10.1103/physrevlett.78.594

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