OPE Analysis of QCD Potential and Determination of Lambda_MSbar

TL;DR

This paper combines lattice and perturbative QCD computations within the operator-product expansion framework to analyze the static QCD potential, determine non-perturbative effects, and accurately relate the lattice scale to Lambda_MSbar.

Contribution

It introduces a novel method to simultaneously extract non-perturbative contributions and Lambda_MSbar from the static QCD potential analysis.

Findings

Large part of the short-distance linear potential is perturbative.

Disfavoring of the delta E_US(r)=0 hypothesis.

Precise determination of r_0 Lambda_MSbar at 0.574 +- 0.042.

Abstract

We analyze the static QCD potential in the distance region 0.1 fm < r < 1 fm. We combine most recent lattice computations and perturbative computations of the potential, in the framework of operator-product expansion (OPE). We determine simultaneously the non-perturbative contribution to the potential, delta E_US(r), and the relation between the lattice scale (Sommer scale) and Lambda_MSbar in the quenched approximation. We find that (1) large part of the short-distance linear potential belongs to the perturbative Wilson coefficient, (2) delta E_US(r) =0 is disfavored, and (3) r_0 Lambda_MSbar^(3-loop)=0.574 +- 0.042 . It provides a new method for precise determination of r_0 Lambda_MSbar.