Jet Broadening in Flowing Matter -- Resummation

TL;DR

This paper derives the leading corrections to jet momentum broadening in a flowing QCD medium, revealing anisotropic effects due to transverse flow and emphasizing the importance of multiple scatterings for accurate descriptions.

Contribution

It introduces a resummed propagator for high-energy partons in flowing matter, capturing leading subeikonal flow effects and providing a more complete description of jet broadening.

Findings

Jet broadening distribution becomes anisotropic with transverse flow.

Odd moments of the distribution are proportional to the medium's transverse velocity.

Multiple scatterings are crucial for accurate modeling in dense nuclear matter.

Abstract

In this work, we obtain the leading corrections to the jet momentum broadening distribution in a QCD medium arising from the transverse flow of the matter. We first derive the single-particle propagator of a highly energetic parton resumming its multiple interactions with the homogeneous flowing matter, explicitly keeping the leading subeikonal flow terms. Then, we use this propagator to obtain the jet broadening distribution and its leading moments. We show that this distribution becomes anisotropic in the presence of transverse flow, since its odd moments are generally non-zero and proportional to the transverse velocity of the medium. Finally, we evaluate several odd moments, which we compare to the corresponding results at first order in opacity, showing that accounting for multiple in-medium scatterings is essential to describe some observables in dense nuclear matter.