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  • Open Access

Particle Correlations in Jets

Wenbin Zhao1,2,3,*, Volker Koch2,†, and Feng Yuan2,‡

  • *Contact author: WenbinZhao@lbl.gov
  • †Contact author: vkoch@lbl.gov
  • ‡Contact author: fyuan@lbl.gov
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Phys. Rev. Lett. 137, 162301 – Published 14 October, 2026

DOI: https://doi.org/10.1103/yscq-npz8

Abstract

We study particle correlations in high energy jets by comparing the measured energy-energy correlator with that constructed from two individual energy flows with respect to the jet axis. This comparison demonstrates that the genuine correlations are stronger at moderate or large angles across all jet energies, indicating that they are coming from correlated splitting. Meanwhile, at small angles, they increase with jet energy, exhibiting a peculiar pattern that can be used to explore jet energy loss in heavy-ion collisions. This method will provide a unique tool to disentangle different physics by comparing the genuine correlations in jet energy-energy correlators between heavy-ion collisions and proton-proton collisions.

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Phys. Rev. Lett. 137, 162301– Published 14 October, 2026
  • Received 1 August 2025
  • Revised 20 July 2026
  • Accepted 24 September 2026
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