On the factorization of overlapping singularities at NNLO

TL;DR

This paper introduces a novel method using non-linear integral transformations to factorize overlapping singularities in NNLO QCD calculations, simplifying the evaluation of complex integrals in collider physics.

Contribution

A new technique for factorizing overlapping singularities in NNLO QCD integrals, applicable to double real and virtual corrections in collider cross-section computations.

Findings

Successfully applied to double real radiation integrals

Demonstrated applicability to two-loop virtual corrections

Simplifies complex multi-dimensional integrals in NNLO calculations

Abstract

Real and virtual corrections in NNLO QCD require multi-dimensional integrals with overlapping singularities. We first review ideas and methods which have been proposed for performing such computations. We then present a new method for the factorization of overlapping singularities based on non-linear integral transformations. We apply this method for the evaluation of all integral topologies which appear in double real radiation corrections in cross-section calculations for the production of a heavy system at hadron colliders. Finally, we demonstrate with typical examples that two-loop virtual corrections are amenable to the same method.