Finite top mass effects for hadronic Higgs production at next-to-next-to-leading order

TL;DR

This paper evaluates the effects of finite top quark mass on Higgs production cross sections at NNLO in QCD, providing a precise approximation that confirms the heavy-top limit's validity for Higgs masses between 100-300 GeV.

Contribution

It introduces a new expansion method to accurately incorporate finite top mass effects at NNLO, validating the heavy-top approximation for Higgs phenomenology.

Findings

Finite top mass effects are negligible (<0.5%) for Higgs masses 100-300 GeV.

The heavy-top limit remains a reliable approximation at NNLO.

The new expansion method improves the precision of Higgs cross section calculations.

Abstract

The first four terms of an expansion in mH^2/mt^2 of the total inclusive cross section for Higgs production in gluon fusion are evaluated through next-to-next-to-leading order QCD. A reliable and precise approximation of the full top mass dependence at NNLO is derived and compared to the frequently used heavy-top limit. It is found that both results agree numerically to better than 0.5% in the Higgs mass range of 100-300 GeV. This validates the higher order results for the inclusive Higgs cross section and justifies the heavy-top limit as a powerful tool for Higgs phenomenology at the LHC and the Tevatron.