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  • Open Access

Gluon radiation inside a flowing medium

Matvey V. Kuzmin1,* and Xoán Mayo López2,†

  • *Contact author: kuzmin.mv19@physics.msu.ru
  • †Contact author: xoan.mayo.lopez@usc.es
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Phys. Rev. D 114, 014037 – Published 20 July, 2026

DOI: https://doi.org/10.1103/4r7w-dqxq

Abstract

We compute the spectrum of gluons emitted by a highly energetic quark inside a flowing QCD medium, focusing on the soft gluon limit at first order in the opacity expansion. Specifically, we derive the leading energy-suppressed corrections to the double differential final parton distribution, and show that they are substantial for both static and flowing matter. In particular, we demonstrate that the corrections due to the transverse flow become large even at moderate energies and flow velocities, affecting drastically both the shape and magnitude of the spectrum. We observe that the final transverse momentum of the emitted gluon tends to align along the flow direction, resulting in a nontrivial azimuthal distribution. These results can be directly implemented into the estimation of multiple observables to get a better understanding of the jet-medium interaction processes in heavy-ion collisions.

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Phys. Rev. D 114, 014037– Published 20 July, 2026
  • Received 5 July 2024
  • Accepted 22 June 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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