Super-Leading Logarithms in $pp\to2$ Jets

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.