Higgs boson pair production in gluon fusion at NLO with full top-quark mass dependence

TL;DR

This paper calculates the Higgs boson pair production cross section in gluon fusion at NLO in QCD, fully accounting for top-quark mass effects, revealing significant deviations from approximation methods.

Contribution

It provides the first full top-quark mass dependent NLO calculation for Higgs pair production, enabling accurate assessment of approximation validity.

Findings

Full top-quark mass dependence significantly affects NLO results.

Substantial deviations found between full calculation and approximations.

Highlights importance of including full mass effects in theoretical predictions.

Abstract

We present the calculation of the cross section and invariant mass distribution for Higgs boson pair production in gluon fusion at next-to-leading order (NLO) in QCD. Top-quark masses are fully taken into account throughout the calculation. The virtual two-loop amplitude has been generated using an extension of the program GoSam supplemented with an interface to Reduze for the integral reduction. The occurring integrals have been calculated numerically using the program SecDec. Our results, including the full top-quark mass dependence for the first time, allow us to assess the validity of various approximations proposed in the literature, which we also recalculate. We find substantial deviations between the NLO result and the different approximations, which emphasizes the importance of including the full top-quark mass dependence at NLO.