On the high-energy behavior of massive QCD amplitudes

TL;DR

This paper develops a factorization formula for high-energy massive QCD amplitudes at two loops, enabling better approximations and resummations of mass effects in scattering processes.

Contribution

It extends existing high-energy factorization results to include massive loops using the method of regions with analytic regulators.

Findings

Derived a new factorization formula for massive QCD amplitudes.

Verified the formula with top-quark pair production amplitudes.

Facilitates approximate calculations and resummation of mass logarithms.

Abstract

In this note, we propose a factorization formula for gauge-theory scattering amplitudes up to two loops in the high-energy boosted limit. Our formula extends existing results in the literature by incorporating the contributions from massive loops. We derive the new ingredients in our formula using the method of regions with analytic regulators for the rapidity divergences. We verify our results with various form factors and the scattering amplitudes for top-quark pair production. Our results can be used to obtain approximate expressions for complicated two-loop massive amplitudes from simpler massless ones, and can be used to resum the mass logarithms to all orders in the coupling constant.