On unifying the description of meson and baryon properties

TL;DR

This paper introduces a covariant Faddeev equation framework that unifies the description of meson and baryon properties, providing predictions for nucleon structure and form factors consistent with experimental observations.

Contribution

It presents a systematic, covariant approach to predict meson and baryon observables using a truncation of Dyson-Schwinger equations, improving the understanding of nucleon structure.

Findings

Predicted nucleon form factors with realistic Q^2-evolution.

Described nucleon mass dependence on current-quark mass.

Revealed negative neutron Dirac form factor due to axial-vector diquark correlations.

Abstract

A Poincare' covariant Faddeev equation is presented, which enables the simultaneous prediction of meson and baryon observables using the leading-order in a truncation of the Dyson-Schwinger equations that can systematically be improved. The solution describes a nucleon's dressed-quark core. The evolution of the nucleon mass with current-quark mass is discussed. A nucleon-photon current, which can produce nucleon form factors with realistic Q^2-evolution, is described. Axial-vector diquark correlations lead to a neutron Dirac form factor that is negative, with r_1^{nu}>r_1^{nd}. The proton electric-magnetic form factor ratio falls with increasing Q^2.