Two-Loop Fermionic Corrections to Heavy-Quark Pair Production: the Quark-Antiquark Channel

TL;DR

This paper presents analytic two-loop fermionic QCD corrections for heavy-quark pair production in the quark-antiquark channel, valid across all kinematic regimes, confirming previous small-mass limit results and providing threshold expansions.

Contribution

It provides the first complete analytic expressions for fermionic two-loop corrections applicable for any Mandelstam invariants and quark mass, including threshold expansions.

Findings

Analytic results valid for all s, t, and m.

Confirmation of previous small-mass limit results.

Threshold expansion of the amplitude near s ~ 4m^2.

Abstract

We evaluate the fermionic two-loop QCD corrections to the heavy-quark pair production process in the quark-antiquark channel. We obtain analytic results which are valid for any value of the Mandelstam invariants s and t, and of the heavy quark mass m. Our findings confirm previous results for the analytic evaluation in the small-mass limit and numerical results for the exact amplitude. We furthermore provide the expansion of the two-loop amplitude at the production threshold s ~ 4m^2.