Threshold Resummation for QCD Hard Scattering

TL;DR

The paper develops a threshold resummation framework for QCD heavy-quark production by extending Drell-Yan methods to include non-Abelian color exchanges. It introduces a three-component factorization into collinear, hard, and soft sectors, with soft-gluon effects governed by a renormalization-group evolution of a color-space anomalous-dimension matrix $\Gamma_{IK}$, enabling exponentiation of large logarithms in moment space. A concrete anomalous-dimension matrix is presented for the $q\bar{q}\to Q\bar{Q}$ channel in a singlet/octet basis, illustrating how color mixing affects resummation. The approach provides controlled, systematic resummation of threshold logarithms for heavy-quark production, improving perturbative predictions and offering a path to more reliable comparisons with data.

Abstract

We describe the resummation of singular distributions at partonic threshold in heavy quark production, generalizing results for Drell-Yan and other electroweak hard-scattering processes.