Effects of initial state fluctuations on jet energy loss

TL;DR

This study investigates how initial state fluctuations in relativistic heavy-ion collisions influence jet energy loss, revealing that fluctuations lead to slightly increased energy loss, especially in non-central collisions and with linear path-length dependence.

Contribution

It introduces a detailed analysis of initial state fluctuations' impact on jet energy loss using hydrodynamic models and NLO pQCD, highlighting the correlation effects.

Findings

Fluctuations cause slightly more jet energy loss compared to smooth initial conditions.

The effect is more pronounced in non-central collisions.

Linear path-length dependence shows larger fluctuation effects.

Abstract

The effect of initial state fluctuations on jet energy loss in relativistic heavy-ion collisions is studied in a 2+1 dimension ideal hydrodynamic model. Within the next-to-leading order perturbative QCD description of hard scatterings, we find that a jet loses slightly more energy in the expanding quark-gluon plasma if the latter is described by the hydrodynamic evolution with fluctuating initial conditions compared to the case with smooth initial conditions. A detailed analysis indicates that this is mainly due to the positive correlation between the fluctuation in the production probability of parton jets from initial nucleon-nucleon hard collisions and the fluctuation in the medium density along the path traversed by the jet. This effect is larger in non-central than in central relativistic heavy ion collisions and also for jet energy loss that has a linear than a quadratic dependence on its path length in the medium.