The enigmatic $\Delta(1600)$ resonance

TL;DR

This paper compares two models of baryon resonances, highlighting different mechanisms behind the $40(1600)$ and $N^*(1440)$ states, emphasizing their distinct origins within hadronic physics.

Contribution

It introduces a model for the $40(1600)$ resonance as a quasi-bound state and contrasts it with a different mechanism for the $N^*(1440)$ resonance.

Findings

The $40(1600)$ is modeled as a $40(1232)$-pion quasi-bound state.

Different mechanisms generate the $40(1600)$ and $N^*(1440)$ resonances.

The models suggest distinct internal structures for these resonances.

Abstract

Our recently proposed model of the $\Delta(1600)$ resonance, in which the dominant component is a quasi-bound state of the $\Delta(1232)$ and the pion, is confronted with a similar model of the $N^*(1440)$ resonance as its counterpart in the P11 partial wave. We stress an essentially different mechanism responsible for generating the two resonances.