Meson and nucleon properties from Dyson-Schwinger QCD

TL;DR

This paper uses Dyson-Schwinger equations in QCD to calculate meson and nucleon properties, successfully describing masses and electromagnetic features, with some limitations near the chiral limit.

Contribution

It introduces a unified approach using rainbow-ladder truncation to compute meson and nucleon observables within Dyson-Schwinger equations, aligning with lattice data for heavy quarks.

Findings

Accurately predicts meson and nucleon masses.

Describes electromagnetic properties consistent with experimental data.

Highlights the role of diquark correlations in nucleon structure.

Abstract

We present selected results from a calculation of meson and nucleon observables in a Green-function approach. A rainbow-ladder truncation of QCD's Dyson-Schwinger equations is used to solve the respective meson, diquark and quark-diquark Bethe-Salpeter equations. It allows for a simultaneous description of meson and nucleon masses and electromagnetic properties from an effective quark-gluon interaction. The results describe a hadronic quark core which agrees with lattice data for heavy quarks whereas pion-cloud effects are missing towards the chiral limit. The neutron's Dirac form factor is negative due to the presence of axial-vector diquark correlations.