Insights into the quark-gluon vertex from lattice QCD and meson spectroscopy

TL;DR

This paper compares quark-gluon vertex models with lattice-QCD data to identify key features for improving interaction models in quantum chromodynamics, emphasizing the importance of a broad, infrared-finite interaction support.

Contribution

It provides a qualitative comparison between lattice-QCD data and interaction models, highlighting features crucial for refining future quark-gluon interaction models beyond the rainbow ladder approximation.

Findings

Realistic interaction should be broad with support at 0.4-0.6 GeV

Interaction should be infrared-finite

Qualitative features guide model tuning

Abstract

By comparing successful quark-gluon vertex interaction models with the corresponding interaction extracted from lattice-QCD data on the quark's propagator, we identify common qualitative features which could be important to tune future interaction models beyond the rainbow ladder approximation. Clearly, a quantitative comparison is conceptually not simple, but qualitatively the results suggest that a realistic interaction should be relatively broad with a strong support at about $0.4-0.6$~GeV and infrared-finite.