Static quark-antiquark potential in the quark-gluon plasma from lattice QCD

TL;DR

This paper non-perturbatively determines the complex static quark-antiquark potential in the quark-gluon plasma using lattice QCD, revealing Debye screening and imaginary parts consistent with perturbative predictions.

Contribution

It introduces a novel Bayesian spectral reconstruction method to extract the potential from lattice QCD at finite temperature.

Findings

Real part of potential close to color singlet free energies

Debye screening observed above T_c

Imaginary part matches perturbative estimates in deconfined phase

Abstract

We present a state-of-the-art determination of the complex valued static quark-antiquark potential at phenomenologically relevant temperatures around the deconfinement phase transition. Its values are obtained from non-perturbative lattice QCD simulations using spectral functions extracted via a novel Bayesian inference prescription. We find that the real part, both in a gluonic medium as well as in realistic QCD with light $u$, $d$ and $s$ quarks, lies close to the color singlet free energies in Coulomb gauge and shows Debye screening above the (pseudo) critical temperature $T_c$. The imaginary part is estimated in the gluonic medium, where we find that it is of the same order of magnitude as in hard-thermal loop resummed perturbation theory in the deconfined phase.