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arXiv · 2509.18647

Charm quark evolution in the early stages of heavy-ion collisions

Mayank Singh·Manu Kurian·Björn Schenke·Sangyong Jeon·Charles Gale
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Abstract

Heavy quarks are predominantly generated at the initial stage of relativistic heavy-ion collisions such that heavy flavor observables have the potential to provide information on the pre-equilibrium medium dynamics. In this study, we investigate the sensitivity of D-meson $R_{AA}$ and $v_2$ to early-time charm quark dynamics in Pb+Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV. We employ the IP-Glasma+MUSIC+UrQMD framework to model the evolution of the bulk medium. Charm quarks are generated using PYTHIA with nuclear parton distribution functions and evolved using Langevin dynamics within MARTINI. We observe that even though there is significant momentum broadening in the earliest stage, D-meson $R_{AA}$ and $v_2$ are only weakly sensitive to pre-equilibrium interactions.

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Mayank Singh, Manu Kurian, Björn Schenke, Sangyong Jeon, Charles Gale. 2025-09-23. Charm quark evolution in the early stages of heavy-ion collisions. https://doi.org/10.1103/7125-lhbl

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