Factorization restoration through Glauber gluons

TL;DR

This paper investigates how Glauber gluons influence the low-energy dynamics of gap-between-jets processes at hadron colliders, revealing their role in restoring factorization and explaining super-leading logarithms.

Contribution

It identifies three-loop Glauber-gluon contributions that restore PDF factorization in gap-between-jets cross sections, clarifying their unambiguous definition without additional regulators.

Findings

Glauber gluons cause super-leading logarithms in jet gaps.

Three-loop Glauber exchanges restore factorization.

Glauber contributions are well-defined without extra regulators.

Abstract

We analyze the low-energy dynamics of gap-between-jets cross sections at hadron colliders, for which phase factors in the hard amplitudes spoil collinear cancellations and lead to double (``super-leading'') logarithmic behavior. Based on a method-of-regions analysis, we identify three-loop contributions from perturbative active-active Glauber-gluon exchanges with the right structure to render the cross section consistent with PDF factorization below the gap veto scale. The Glauber contributions we identify are unambiguously defined without regulators beyond dimensional regularization.