Potential NRQCD: an effective theory for heavy quarkonium

TL;DR

This paper develops an effective field theory called potential NRQCD to analyze heavy quarkonium systems at short distances, systematically including non-potential effects and addressing infrared renormalon issues.

Contribution

It introduces a new effective theory framework for heavy quarkonium, defining the potential and systematically incorporating retardation effects and renormalon cancellations.

Findings

Short-distance behavior of gluonic excitation energies determined.

Infrared renormalons cancel in the effective theory.

Potential defined within the effective field theory framework.

Abstract

Within an effective field theory framework we study heavy-quark--antiquark systems with a typical distance between the heavy quark and the antiquark smaller than $1/\Lambda_{\rm QCD}$. A suitable definition of the potential is given within this framework, while non-potential (retardation) effects are taken into account in a systematic way. We explore different physical systems. Model-independent results on the short distance behavior of the energies of the gluonic excitations between static quarks are obtained. Finally, we show how infrared renormalons affecting the static potential get cancelled in the effective theory.