System-size dependence of $\gamma$-jet modifications in heavy-ion collisions

TL;DR

This study uses the Linear Boltzmann Transport model to analyze how the size of the collision system affects gamma-jet modifications in heavy-ion collisions, revealing greater medium effects in larger, more central systems.

Contribution

It provides the first systematic analysis of system-size dependence of gamma-jet modifications using the LBT model across different collision systems and centralities.

Findings

Central collisions show wider transverse asymmetry distributions.

Jet shape broadening is more pronounced in central collisions.

Greater gamma-jet imbalance observed in larger, more central systems.

Abstract

Medium modifications of the $\gamma$-triggered jets are investigated with the Linear Boltzmann Transport (LBT) model in heavy-ion collisions with varying system sizes, focusing on centrality dependence in Pb+Pb and Xe+Xe collisions at the LHC. Our numerical results reveal that jets produced in central collisions exhibit a wider transverse asymmetry ($A_N^y$) distribution, a broader jet shape, and a more pronounced $\gamma$-jet transverse momentum imbalance ($X_{J\gamma}=p_T^{\rm jet}/p_T^\gamma$) compared to peripheral collisions. These effects arise from the longer path length and stronger jet-medium interactions in central collisions, leading to enhanced jet quenching and medium response. Our findings demonstrate that the magnitude of $\gamma$-jet modifications is sensitive to the size and centrality of the collision system, with larger systems inducing more significant alterations due to increased energy loss and medium feedback.