Monte Carlo Simulation for Elastic Energy Loss of Hard Partons in a Hydrodynamical Background

TL;DR

This paper presents a Monte Carlo simulation of elastic energy loss for high-energy partons in a quark-gluon plasma, comparing different hydrodynamical models and experimental data from RHIC and LHC.

Contribution

It introduces a detailed Monte Carlo approach to model elastic energy loss of partons in a hydrodynamical medium using leading-order pQCD and compares results with experimental data.

Findings

Incoherent elastic energy loss does not match the observed angular suppression.

Initial state density fluctuations have minimal impact.

Model extrapolation from RHIC to LHC is discussed.

Abstract

We have developed a Monte Carlo simulation describing the $2 \rightarrow 2$ scatterings of perturbatively produced, non-eikonally propagating high-energy partons with the quarks and gluons of the expanding QCD medium created in ultrarelativistic heavy ion collisions. The partonic scattering rates are computed in leading-order perturbative QCD (pQCD), while three different hydrodynamical scenarios are used to model the strongly interacting medium. We compare our results and tune the model with the neutral pion suppression observed in $\sqrt{s_{NN}}=200$ GeV Au+Au collisions at the BNL-RHIC. We find the incoherent nature of elastic energy loss incompatible with the measured angular dependence of the suppression. The effects of the initial state density fluctuations of the bulk medium are found to be small. Also the extrapolation from RHIC to the LHC is discussed.