Static quark anti-quark interactions at non-zero temperature from lattice QCD

TL;DR

This study uses lattice QCD to analyze static quark-antiquark interactions at non-zero temperature, comparing lattice results with perturbation theory and extracting spectral functions through multiple methods.

Contribution

It introduces a comprehensive analysis of Wilson line correlators at finite temperature using various spectral reconstruction techniques, advancing understanding of quark interactions in hot QCD matter.

Findings

Wilson line correlators agree with HTL predictions at high temperatures

Spectral functions show a well-defined ground state peak at certain conditions

Multiple spectral reconstruction methods yield consistent results

Abstract

We study the interactions of a static quark antiquark pair at non-zero temperature using realistic 2+1 flavor lattice QCD calculations. The study consists of two parts: the first investigates the properties of Wilson line correlators in Coulomb gauge and compares to predictions of hard-thermal loop perturbation theory. As a second step we extract the spectral functions underlying the correlators using four conceptually different methods: spectral function fits, a HTL inspired fit for the correlation function, Pad\'e rational approximation and the Bayesian BR spectral reconstruction. We find that our high statistics Euclidean lattice data are amenable to different hypotheses for the shapes of the spectral function and we compare the implications of each analysis method for the existence and properties of a well defined ground state spectral peak.