Parton energy loss in a classical strongly coupled QGP

TL;DR

This study uses molecular dynamics simulations to analyze how heavy quarks lose energy in a classical, strongly coupled quark-gluon plasma, revealing diffusive behavior and mass-dependent drag effects.

Contribution

It introduces a classical non-relativistic Coulomb gas model to simulate energy loss mechanisms in a strongly coupled QGP, connecting classical results to sQGP conditions.

Findings

Energy loss is diffusive and Langevin-like due to rapid electric force decorrelation.

Drag coefficient varies with heavy quark mass, diffusion constant remains unchanged.

Fractional collisional energy loss exceeds leading order estimates due to core repulsion.

Abstract

We investigate the energy loss of heavy quarks in the gas, liquid and solid phase of a classical quark-gluon plasma (cQGP) using molecular dynamics simulations. The model consists of massive quarks and gluons interacting as a classical non-relativistic colored Coulomb gas. We show that the electric force decorrelates on a short time scale causing the energy loss to be mostly diffusive and langevin-like in the cQGP. We find that the drag coefficient changes with the heavy quark mass, while the diffusion constant does not. The fractional collisional energy loss is much larger than the leading order estimates from a wQGP because of the core repulsion. Following recent suggestions, we show how the cQGP results can be translated to the sQGP results in the $T=(1-3)T_c$ range.