Quark-gluon vertex with 2 flavours of O(a) improved Wilson fermions

TL;DR

This study investigates the infrared behavior of the quark-gluon vertex with two flavors of improved Wilson fermions, revealing significant infrared enhancement of form factors as chiral and continuum limits are approached.

Contribution

It provides the first detailed analysis of the Landau-gauge quark-gluon vertex with 2 flavors of O(a) improved Wilson fermions across multiple lattice spacings and quark masses.

Findings

All form factors show significant infrared strength.

The leading form factor lambda_1 is enhanced in the infrared.

Infrared enhancement increases as chiral and continuum limits are approached.

Abstract

We study the Landau-gauge quark-gluon vertex with 2 flavours of O(a)improved Wilson fermions, for several lattice spacings and quark masses. In the limit of vanishing gluon momentum, we find that all nonzero form factors have a significant infrared strength, and that the leading form factor lambda_1, multiplying the tree-level vertex structure, is significantly enhanced in the infrared compared to the quenched case. We find that all form factors are further enhanced in the infrared as the chiral and continuum limits are approached.