Thermalization of quark-gluon matter with the elastic scattering of gqq, gqqbar and gqbarqbar

TL;DR

This paper investigates how elastic scattering processes involving gluons and quarks contribute to the thermalization of quark-gluon matter in high-energy collisions, using perturbative QCD and transport equations.

Contribution

It derives squared amplitudes for elastic gqq, gqqbar, and gqbarqbar scatterings and demonstrates their role in accelerating quark-gluon matter thermalization.

Findings

Elastic scatterings shorten thermalization time.

Transport equations model anisotropic distributions.

Perturbative QCD provides squared amplitudes.

Abstract

The elastic scattering of gqq, gqqbar and gqbarqbar and the thermalization of quark-gluon matter are studied. According to Feynman diagrams at the tree level, squared amplitudes for the elastic gqq scattering and the elastic gqqbar scattering are derived in perturbative QCD. Transport equations including the squared amplitudes for the elastic gqq, gqqbar and gqbarqbar scattering are established. Corresponding to anisotropic gluon and quark distributions created in central Au-Au collisions at RHIC, solutions of the transport equations show that thermalization time of quark matter can be shortened by the elastic gqq, gqqbar and gqbarqbar scattering.