Jet quenching parameter \hat q in the stochastic QCD vacuum with Landau damping

TL;DR

This paper calculates the jet quenching parameter in the quark-gluon plasma by considering Landau damping of soft modes, using the stochastic vacuum model in SU(3) quenched QCD, and compares results with perturbative QCD.

Contribution

It introduces a novel calculation of the jet quenching parameter based on Landau damping within the stochastic vacuum model, providing temperature-dependent results.

Findings

Jet quenching parameter increases from 0 to ~1.8 GeV^2/fm as temperature rises from T_c to 900 MeV.

Results depend on gluon condensate, vacuum correlation length, and gluon Debye mass.

Comparison shows differences with perturbative QCD predictions.

Abstract

We argue that the radiative energy loss of a parton traversing the quark-gluon plasma is determined by Landau damping of soft modes in the plasma. Using this idea, we calculate the jet quenching parameter of a gluon. The calculation is done in SU(3) quenched QCD within the stochastic vacuum model. At the LHC-relevant temperatures, the result depends on the gluon condensate, the vacuum correlation length, and the gluon Debye mass. Numerically, when the temperature varies from T=T_c to T=900 MeV, the jet quenching parameter rises from \hat q=0 to approximately 1.8 GeV^2/fm. We compare our results with the predictions of perturbative QCD and other calculations.