Parton radiative processes and pressure isotropization in relativistic heavy ion collisions

TL;DR

This paper investigates how radiative 2<->3 processes influence the thermalization and pressure isotropization of Quark-Gluon Plasma in heavy ion collisions, highlighting their significant role in kinetic equilibration.

Contribution

It demonstrates that radiative processes significantly enhance thermalization and lead to a universal asymptotic evolution regardless of initial conditions.

Findings

2<->3 processes increase thermalization levels

Pressure anisotropy evolution scales with coupling constant

Initial conditions converge to similar evolution with radiative processes

Abstract

The impact of radiative processes on kinetic equilibration is studied via a radiative transport model. The 2 <-> 3 processes can significantly increase the level of thermalization. These processes lead to an approximate coupling constant scaling of the evolution of the pressure anisotropy qualitatively different from the case with only 2 -> 2 partonic processes. Furthermore, thermal and Color Glass Condensate motivated initial conditions are shown to share the same asymptotic evolution when 2 <-> 3 processes are included. This emphasizes the unique role of radiative processes in Quark-Gluon Plasma thermalization.