Locally finite two-loop QCD amplitudes from IR universality for electroweak production

TL;DR

This paper presents a method for efficiently computing two-loop QCD corrections to electroweak processes by utilizing infrared universality, leading to simplified subtractions and improved numerical integration.

Contribution

It introduces a new infrared subtraction scheme based on form-factor integrands that reduces complexity and enhances computational efficiency for two-loop QCD calculations.

Findings

Subtractions are expressed as known form-factor integrands.

The method simplifies two-loop QCD amplitude computations.

Efficient numerical integration of corrected amplitudes is achieved.

Abstract

We describe the implementation of infrared subtractions for two-loop QCD corrections to quark-antiquark annihilation to electroweak final states. The subtractions are given as form-factor integrands whose integrals are known. The resulting subtracted amplitudes are amenable to efficient numerical integration. Our procedure is based on the universality of infrared singularities and requires a relatively limited set of subtractions, whose number grows as the number of two-loop diagrams, rather than with the number of singular regions of integration.