English

Flavor dependence of Energy-energy correlators

High Energy Physics - Phenomenology 2025-03-12 v2 Nuclear Theory

Abstract

Energy-energy correlators (EECs) within high energy jets serve as a key experimentally accessible quantity to probe the scale and structure of the quark-gluon plasma (QGP) in relativistic heavy-ion collisions. The CMS Collaboration's first measurement of the modification to the EEC within single inclusive jets in Pb+Pb collisions relative to p+p collisions reveals a significant enhancement at small angles, which may arise from jet transverse momentum pTp_T selection biases due to jet energy loss. We investigate the dependence of jet EECs on the flavor of the initiating parton. The EEC distribution of a gluon jet is broader and the peak of transition from perturbative to non-perturbative regime occurs at a larger angle than a quark jet. Such flavor dependence leads to the different EECs for γ\gamma-jets and single inclusive jets due to their different flavor composition. It is also responsible for a colliding energy dependence of EECs of single inclusive jets at fixed jet energy. We also investigate the impact of flavor composition variation on the pTp_T dependence of the jet EEC. We further propose that a change in the gluon jet fraction in A+A collisions compared to p+p can also contribute to a non-negligible enhancement of the medium modified EEC at small angles. Using the \textsc{Jewel} model, we predict the reduction of the gluon jet fraction in A+A collisions and estimate its impact on the EEC.

Keywords

Cite

@article{arxiv.2502.11406,
  title  = {Flavor dependence of Energy-energy correlators},
  author = {Liliana Apolinário and Raghav Kunnawalkam Elayavalli and Nuno Olavo Madureira and Jun-Xing Sheng and Xin-Nian Wang and Zhong Yang},
  journal= {arXiv preprint arXiv:2502.11406},
  year   = {2025}
}

Comments

This version includes revised figures and additional references