Deconfinement critical point of heavy quark effective lattice theories

TL;DR

This study uses effective lattice theories derived from QCD to analyze the deconfinement critical point for heavy quarks, finding good agreement with full QCD simulations and assessing the validity of approximation methods.

Contribution

It provides a detailed analysis of the deconfinement critical point using effective theories and compares results with full QCD simulations to validate approximation techniques.

Findings

Critical quark mass for deconfinement transition identified

Agreement with full QCD simulations at certain orders

Assessment of the validity of strong coupling and hopping expansions

Abstract

Effective three-dimensional Polyakov loop theories derived from QCD by strong coupling and hopping expansions are valid for heavy quarks and can also be applied to finite chemical potential $\mu$, due to their considerably milder sign problem. We apply the Monte-Carlo method to the $N_f=1,2$ effective theories up to $\mathcal{O}(\kappa^4)$ in the hopping parameter at $\mu=0$ to determine the critical quark mass, at which the first-order deconfinement phase transition terminates. The critical end point obtained from the effective theory to order $\mathcal{O}(\kappa^2)$ agrees well with 4-dimensional QCD simulations with a hopping expanded determinant by the WHOT-QCD collaboration. We also compare with full QCD simulations and thus obtain a measure for the validity of both the strong coupling and the hopping expansion in this regime.