Medium Modification of \gamma-jets in High-energy Heavy-ion Collisions

TL;DR

This paper studies how medium effects modify gamma-tagged jets in high-energy heavy-ion collisions using a Boltzmann transport model, reproducing experimental data and revealing significant changes in jet structure.

Contribution

It introduces a comprehensive model including recoiled medium partons, improving understanding of jet modifications and matching experimental gamma-jet asymmetry data.

Findings

Recoiled medium partons reduce net jet energy loss.

Reproduces experimental gamma-jet asymmetry and survival rate.

Medium modifications significantly affect jet fragmentation and energy flow.

Abstract

Medium modification of \gamma-tagged jets in high-energy heavy-ion collisions is investigated within a Linearized Boltzmann Transport model for jet propagation that includes both elastic parton scattering and induced gluon emission. Inclusion of recoiled medium partons in the reconstruction of partonic jets is found to significantly reduce the net jet energy loss. Experimental data on \gamma-jet asymmetry and survival rate in Pb + Pb collisions at \sqrt{s}=2.76 TeV can be reproduced. Medium modifications of reconstructed jet fragmentation function, transverse profile and energy flow outside the jet-cone are found to be sizable especially for \gamma-tagged jets with small values of x=p_T^{jet}/p_T^\gamma.