The deconfinement phase transition in the Hamiltonian approach to Yang--Mills theory in Coulomb gauge

TL;DR

This paper investigates the deconfinement phase transition in SU(2) Yang--Mills theory using a Hamiltonian approach in Coulomb gauge, revealing changes in ghost and gluon properties and estimating the transition temperature.

Contribution

It introduces a Hamiltonian Coulomb gauge framework with a quasi-particle picture to analyze the deconfinement transition in Yang--Mills theory.

Findings

Ghost form factor remains infrared divergent with halved exponent above transition

Gluon energy becomes infrared finite in deconfined phase

Deconfinement temperature estimated between 275 and 290 MeV

Abstract

The deconfinement phase transition of SU(2) Yang--Mills theory is investigated in the Hamiltonian approach in Coulomb gauge assuming a quasi-particle picture for the grand canonical gluon ensemble. The thermal equilibrium state is found by minimizing the free energy with respect to the quasi-gluon energy. Above the deconfinement phase transition the ghost form factor remains infrared divergent but its infrared exponent is approximately halved, while the gluon energy, being infrared divergent in the confined phase, becomes infrared finite in the deconfined phase. For the effective gluon mass we find a critical exponent of 0.37. Using the lattice results for the gluon propagator to fix the scale, the deconfinement transition temperature is obtained in the range of 275 to 290 MeV.