Sonic Mach Cones Induced by Fast Partons in a Perturbative Quark-Gluon Plasma

TL;DR

This paper models how a fast-moving parton deposits energy in a weakly coupled quark-gluon plasma, resulting in observable sonic Mach cones and wakes, using perturbative and hydrodynamical methods.

Contribution

It provides a derivation of the energy-momentum distribution caused by a fast parton and demonstrates the formation of Mach cones in a perturbative quark-gluon plasma.

Findings

Presence of sonic Mach cones in the plasma

Energy and momentum deposition profiles

Dissipative wake formation behind the parton

Abstract

We derive the space-time distribution of energy and momentum deposited by a fast parton traversing a weakly coupled quark-gluon plasma by treating the fast part on as the source of an external color field perturbing the medium. We then use our result as a source term for the linearized hydrodynamical equations of the medium. We show that the solution contains a sonic Mach cone and a dissipative wake if the parton moves at a supersonic speed.