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arXiv · 2601.07570

EPOS4 Model Predictions for Global Observables in Pb-Pb Collisions at $\sqrt{s_{NN}}$ = 5.36 TeV

Abstract

The study of the Quark-Gluon Plasma (QGP), a deconfined state of nuclear matter, remains a central focus of high-energy heavy-ion collision experiments. The recent operation of the Large Hadron Collider (LHC) in Run 3 at the new center-of-mass energy of $\sqrt{s_{NN}}=5.36$ TeV necessitates theoretical predictions to characterize the energy dependence and bulk properties of the medium. In this study, we present comprehensive EPOS4 model predictions for key global observables in Pb-Pb collisions at $5.36$ TeV. We focus on the centrality dependence of the charged-particle pseudorapidity density ($dN_{ch}/dη$), integrated yields ($dN/dy$), mean transverse momentum ($\langle p_{T}\rangle$) for light-flavor hadrons ($π^{\pm}, K^{\pm}, p(\bar{p})$), and the charged particle nuclear modification factor ($R_{AA}$). The EPOS4 framework successfully captures the strong mass-dependent rise of $\langle p_{T}\rangle$ with multiplicity, a definitive signature of collective radial flow. Furthermore, the predicted charged hadron $R_{AA}$ demonstrates a clear suppression, consistent with energy loss mechanisms incorporated into the model. By comparing these predictions to existing $5.02$ TeV data, we demonstrate that the EPOS4 model offers a consistent and robust description of heavy-ion dynamics, projecting minimal energy evolution for these bulk and hard-probe observables between the two energies.

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Hirak Kumar Koley, Subikash Choudhury, Mitali Mondal. 2026-01-12. EPOS4 Model Predictions for Global Observables in Pb-Pb Collisions at $\sqrt{s_{NN}}$ = 5.36 TeV. https://arxiv.org/abs/2601.07570

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