The Rapidity Renormalization Group

TL;DR

This paper presents a systematic method for resumming large logarithms in gauge theory observables involving rapidity differences, demonstrated through jet broadening calculations that match experimental data.

Contribution

It introduces the Rapidity Renormalization Group formalism for resummation involving rapidities, extending existing techniques to a broader class of gauge theory observables.

Findings

Resummation formalism successfully applied to jet broadening.

Next-to-leading logarithmic order calculations match experimental data.

Provides operator definition and closed-form expressions for cross sections.

Abstract

We introduce a systematic approach for the resummation of perturbative series which involve large logarithms not only due to large invariant mass ratios but large rapidities as well. Series of this form can appear in a variety of gauge theory observables. The formalism is utilized to calculate the jet broadening event shape in a systematic fashion to next to leading logarithmic order. An operator definition of the factorized cross section as well as a closed form of the next-to leading log cross section are presented. The result agrees with the data to within errors.