Heavy quark pair production in gluon fusion at next-to-next-to-leading ${\cal O}(\alpha_s^4)$ order: One-loop squared contributions

TL;DR

This paper computes the complete one-loop squared contributions at NNLO for heavy-quark pair production via gluon fusion, providing a crucial step towards precise QCD predictions with full mass dependence.

Contribution

It provides the full mass-dependent one-loop squared NNLO corrections for gluon fusion heavy-quark production, completing the set of NNLO contributions for this process.

Findings

Results are presented in a compact, closed form.

Full mass dependence is retained in the calculations.

Completes the NNLO QCD correction set for heavy-flavor hadroproduction.

Abstract

We calculate the next-to-next-to-leading order ${\cal O}(\alpha_s^4)$ one-loop squared corrections to the production of heavy-quark pairs in the gluon-gluon fusion process. Together with the previously derived results on the $q \bar{q}$ production channel the results of this paper complete the calculation of the one-loop squared contributions of the next-to-next-to-leading order ${\cal O}(\alpha_s^4)$ radiative QCD corrections to the hadroproduction of heavy flavors. Our results, with the full mass dependence retained, are presented in a closed and very compact form, in dimensional regularization.