Heavy quark correlators in Instanton Liquid Model with perturbative corrections

TL;DR

This paper investigates how instanton effects and perturbative gluon corrections influence heavy quark correlators and potentials within the QCD vacuum, with implications for heavy quarkonium phenomenology.

Contribution

It introduces a combined instanton and perturbative approach to heavy quark correlators and potentials, incorporating screening effects and a Yukawa-type potential approximation.

Findings

Mass shifts due to instanton and perturbative contributions.

Screened one-gluon exchange potential modeled by a Yukawa form.

Implications for heavy quarkonium phenomenology discussed.

Abstract

In the present work we consider the influence on the heavy quark correlators due to the instanton background in the framework of instanton liquid model (ILM) of QCD vacuum by taking into account also the perturbative gluon effects. For a single heavy quark this leads to the mass shift due to the direct-instanton nonperturbative and ILM modified perturbative contributions, respectively. In the heavy quark-antiquark ($Q\bar{Q}$) sector we obtain the potential consisting the direct instanton induced part and the one-gluon exchange (OGE) perturbative part which is screened at large distances due to the nonperturbative dynamics. At the region of interest corresponding to the heavy quark physics the screening effect in OGE can be well approximated by a Yukawa-type potential in terms of the dynamically generated gluon mass. A possible implication of the present studies to the phenomenology of heavy quarkonium is also discussed.