Real corrections to Higgs boson pair production at NNLO in the large top quark mass limit

TL;DR

This paper calculates NNLO corrections to Higgs boson pair production considering the large top quark mass limit, providing key expansion terms that improve theoretical predictions in particle physics.

Contribution

It introduces four new expansion terms in 1/m_t^2 for the NNLO cross section, enhancing approximation methods across the full kinematic range.

Findings

Good convergence below the top quark threshold

Provides detailed phase-space master integrals

Improves accuracy of theoretical predictions

Abstract

In this paper we consider the next-to-next-to-leading order total cross section of Higgs boson pair production in the large top quark mass limit and compute four expansion terms in $1/m_t^2$. Good convergence is observed below the top quark threshold, which makes our results a valuable input for approximation methods which aim for next-to-next-to-leading order corrections over the whole kinematic range. We present details on various steps of our calculation; in particular, we provide results for three- and four-particle phase-space master integrals and describe in detail the evaluation of the collinear counterterms.