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arXiv · 1502.04719

Decoupling of heavy quarks at four loops and effective Higgs-fermion coupling

Tao Liu·Matthias Steinhauser
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Abstract

We compute the decoupling constant $ζ_m$ relating light quark masses of effective $n_l$-flavour QCD to $(n_l+1)$-flavour QCD to four-loop order. Immediate applications are the evaluation of the $\overline{\rm MS}$ charm quark mass with five active flavours and the bottom quark mass at the scale of the top quark or even at GUT scales. With the help of a low-energy theorem $ζ_m$ can be used to obtain the effective coupling of a Higgs boson to light quarks with five-loop accuracy. We briefly discuss the influence on $Γ(H\to b\bar{b})$.

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Tao Liu, Matthias Steinhauser. 2015-07-16. Decoupling of heavy quarks at four loops and effective Higgs-fermion coupling. https://doi.org/10.1016/j.physletb.2015.05.023

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