Super-Leading Logarithms in $pp\to2$ Jets

TL;DR

This paper investigates super-leading logarithms in jet production at hadron colliders, revealing their significant numerical impact on cross sections and emphasizing the need to include these effects in precision calculations.

Contribution

It provides the first comprehensive analysis of super-leading logarithms in hadronic cross sections, including all partonic channels and interference effects, highlighting their importance.

Findings

Super-leading logarithms can significantly affect the $pp\to 2$ jets cross section.

Interference terms in $q\bar q\to q\bar q$ scattering are only linearly suppressed in $1/N_c$.

Super-leading logarithms are numerically important at small veto scales $Q_0$.

Abstract

Jet observables at hadron colliders feature ''super-leading'' logarithms, double-logarithmic corrections resulting from a breakdown of color coherence due to complex phases in hard-scattering amplitudes. While these effects only arise in high orders of perturbation theory and are suppressed in the large-$N_c$ limit, they formally constitute leading logarithmic corrections to the cross sections. We present the first analysis of the corresponding contributions to a hadronic cross section, including all partonic channels and interference effects. Interestingly, some interference terms in partonic $q\bar q\to q\bar q$ scattering are only linearly suppressed in $1/N_c$. Our results for the $pp\to 2$ jets gap-between-jets cross section demonstrate the numerical importance of super-leading logarithms for small values of the veto scale $Q_0$, showing that these contributions should be accounted for in precision studies of such observables.