Gluon Mass in Landau Gauge QCD

TL;DR

This paper investigates the gluon propagator in Landau gauge QCD, finding an infrared gluon mass around 651 MeV, but the data suggests a momentum-dependent mass decreasing with energy, incompatible with a constant ultraviolet mass.

Contribution

It introduces a detailed analysis of gluon mass behavior in Landau gauge QCD, including infrared, ultraviolet, and momentum-dependent scenarios, with new insights into the mass's momentum dependence.

Findings

Infrared gluon mass approximately 651 MeV.

Ultraviolet data incompatible with a constant mass.

Momentum-dependent mass decreases with momentum, following a $q^2 \, \ln q^2$ pattern.

Abstract

The interpretation of the Landau gauge lattice gluon propagator as a massive type bosonic propagator is investigated for i) an infrared constant gluon mass; ii) an ultraviolet constant gluon mass; iii) a momentum dependent mass. We find that the infrared data can be associated with a massive propagator with a constant gluon mass of 651(12) MeV, but the ultraviolet lattice data is not compatible this type of propagator. The scenario of a momentum dependent gluon mass gives a decreasing mass with the momentum, starting from a value of $\sim 630$ MeV in the infrared region and suggesting a $q^2 \ln q^2$ dependence for momenta above 1 GeV.