Thermalization in Heavy-Ion Collisions

TL;DR

This paper introduces a model for nucleon isotropization and thermalization in heavy-ion collisions, emphasizing the role of momentum transfer randomization during fireball evolution, leading to partial thermalization.

Contribution

It presents a novel model based on momentum transfer distribution assumptions to explain nucleon thermalization in heavy-ion collisions.

Findings

Results show partial isotropization of nucleon momenta.

The model derives nonequilibrium distribution functions.

Momentum smearing correlates with thermalization levels.

Abstract

We propose a model for isotropization and corresponding thermalization in a nucleon system created in the collision of two nuclei. The model is based on the assumption: during the fireball evolution, two-particle elastic and inelastic collisions give rise to the randomization of the nucleon-momentum transfer which is driven by a proper distribution. As a first approximation, we assume a homogeneous distribution where the values of the momentum transfer is bounded from above. These features have been shown to result in a smearing of the particle momenta about their initial values and, as a consequence, in their partial isotropization and thermalization. The nonequilibrium single-particle distribution function and single-particle spectrum which carry a memory about initial state of nuclei have been obtained.