Pion cloud effects on baryon masses

Abstract

In this work we explore the effect of pion cloud contributions to the mass of the nucleon and the Δ baryon. To this end we solve a coupled system of Dyson–Schwinger equations for the quark propagator, a Bethe–Salpeter equation for the pion and a three-body Faddeev equation for the baryons. In the quark–gluon interaction we explicitly resolve the term responsible for the back-coupling of the pion onto the quark, representing rainbow-ladder like pion cloud effects in bound states. We study the dependence of the resulting baryon masses on the current quark mass and discuss the internal structure of the baryons in terms of a partial wave decomposition. We furthermore determine values for the nucleon and Δ sigma-terms.