Operator product expansion and quark condensate from Lattice QCD in coordinate space

TL;DR

This paper introduces a new lattice QCD method to determine the quark condensate by analyzing the operator product expansion of the quark propagator at short distances, yielding results consistent with previous approaches.

Contribution

A novel lattice QCD approach using the operator product expansion to accurately extract the quark condensate in coordinate space.

Findings

Quark condensate value: -(265±5±22 MeV)^3 at 2 GeV

Method agrees with other determination approaches

Performed on quenched lattice with improved Wilson action

Abstract

We present a Lattice QCD determination of the chiral quark condensate based on a new method. We extract the quark condensate from the operator product expansion of the quark propagator at short euclidean distances, where it represents the leading contribution in the chiral limit. From this study we obtain <\bar q q>^ms(2 GeV)=-(265+-5+-22 MeV)^3$, in good agreement with determinations of this quantity based on different approaches. The simulation is performed by using the O(a)-improved Wilson action at beta=6.45 on a volume 32^3\times70 in the quenched approximation.