Determination of light quark masses in QCD

TL;DR

This paper discusses an improved method using QCD sum rules to determine light quark masses with greater accuracy, reducing previous systematic uncertainties and achieving results with better than 8% precision.

Contribution

The paper introduces a breakthrough technique that significantly reduces systematic uncertainties in light quark mass determination via QCD sum rules.

Findings

Achieved light quark masses with better than 8% accuracy.

Reduced systematic uncertainties in the hadronic resonance sector.

Enhanced the reliability of QCD sum rule methods for quark mass measurements.

Abstract

The standard procedure to determine (analytically) the values of the quark masses is to relate QCD two-point functions to experimental data in the framework of QCD sum rules. In the case of the light quark sector, the ideal Green function is the pseudoscalar correlator which involves the quark masses as an overall multiplicative factor. For the past thirty years this method has been affected by systematic uncertainties originating in the hadronic resonance sector, thus limiting the accuracy of the results. Recently, a major breakthrough has been made allowing for a considerable reduction of these systematic uncertainties and leading to light quark masses accurate to better than 8%. This procedure will be described in this talk for the up-, down-, strange-quark masses, after a general introduction to the method of QCD sum rules.