In-medium static quark potential from spectral functions on realistic HISQ ensembles

TL;DR

This study investigates the in-medium static quark potential using spectral functions derived from lattice QCD ensembles with dynamical HISQ flavors across a wide temperature range, employing multiple reconstruction methods.

Contribution

It introduces a comprehensive analysis of quark-antiquark interactions in a thermal medium using spectral functions and compares three different spectral reconstruction techniques.

Findings

Spectral functions reveal temperature-dependent peak positions and widths.

Multiple reconstruction methods provide consistent insights into in-medium quark potentials.

The study assesses the limitations of each spectral analysis approach.

Abstract

We explore the interactions between a quark anti-quark pair in a thermal medium based on lattice QCD ensembles with $N_f = 2+1$ dynamical HISQ flavors. Our dataset spans the phenomenologically relevant temperature range between T=140MeV-2GeV based on lattice sizes $N_\tau=10,12$ and $16$, with an aspect ratio of $N_\sigma/N_\tau=4$. The peak position $\Omega$ and the width $\Gamma$ of the spectral function of Wilson-line correlators in Coulomb gauge is computed. We assess the information content in the correlation functions and deploy three complementary strategies to reconstruct spectral information: model fits, Pad\'e approximation and the Bayesian BR method. Limitations of each approach are carefully assessed.