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arXiv · 2001.06295

Quark mass effects in two-loop Higgs amplitudes

Abstract

We provide two two-loop amplitudes relevant for precision Higgs physics. The first is the two-loop amplitude for Higgs boson production through gluon fusion with exact dependence on the top quark mass up to squared order in the dimensional regulator $\epsilon$. The second result we provide is the two-loop amplitude for the decay of a Higgs boson into a pair of massive bottom quarks through the Higgs-to-gluon coupling in the infinite top mass limit. Both amplitudes are computed by finding canonical bases of master integrals, which we evaluate explicitly in terms of harmonic polylogarithms. We obtain the bare, renormalized and IR-subtracted amplitude and provide the results in terms of building blocks suitable to changing renormalization schemes.

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Charalampos Anastasiou, Nicolas Deutschmann, Armin Schweitzer. 2020-01-17. Quark mass effects in two-loop Higgs amplitudes. https://doi.org/10.1007/jhep07(2020)113

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