Initial conditions for hydrodynamics from weakly coupled pre-equilibrium evolution

TL;DR

This paper develops a Green function approach using effective kinetic theory to model the pre-equilibrium evolution of energy and flow perturbations in heavy-ion collisions, bridging initial conditions to hydrodynamics.

Contribution

It introduces a Green function that propagates initial energy-momentum perturbations through pre-equilibrium stages within weakly coupled QCD.

Findings

Green function for pre-equilibrium evolution derived

Modeling of initial conditions to hydrodynamics transition achieved

Framework applicable to weakly coupled QCD simulations

Abstract

We use leading order effective kinetic theory to simulate the pre\nobreakdash-equilibrium evolution of transverse energy and flow perturbations in heavy-ion collisions. We provide a Green function which propagates the initial perturbations of the energy-momentum tensor to a time when hydrodynamics becomes applicable. With this map, the pre-thermal evolution from saturated nuclei to hydrodynamics can be modeled in the framework of weakly coupled QCD.