Disentangling the timescales behind the non-perturbative heavy quark potential

TL;DR

This paper investigates the complex structure of the heavy quark potential by analyzing the spectral peaks of Wilson loops, revealing that early time effects influence the potential shape and indicating a transition to a deconfined plasma.

Contribution

It introduces an improved spectral peak distribution that accounts for non-potential effects, refining the extraction of the heavy quark potential from lattice QCD data.

Findings

Early time effects significantly alter spectral peak shapes.

The refined potential suggests a transition to a deconfined screening plasma.

The method improves the understanding of non-perturbative heavy quark interactions.

Abstract

The static part of the heavy quark potential has been shown to be closely related to the spectrum of the rectangular Wilson loop. In particular the lowest lying positive frequency peak encodes the late time evolution of the two-body system, characterized by a complex potential. While initial studies assumed a perfect separation of early and late time physics, where a simple Lorentian (Breit-Wigner) shape suffices to describe the spectral peak, we argue that scale decoupling in general is not complete. Thus early time, i.e. non-potential effects, significantly modify the shape of the lowest peak. We derive on general grounds an improved peak distribution that reflects this fact. Application of the improved fit to non-perturbative lattice QCD spectra now yields a potential that is compatible with a transition to a deconfined screening plasma.