Results of Nucleon Resonance Extraction via Dynamical Coupled-Channels Analysis from Collaboration@EBAC

TL;DR

This paper reviews a comprehensive dynamical coupled-channels analysis of meson production reactions off nucleons, revealing new features of nucleon excitations as resonant particles arising from complex multi-channel dynamics.

Contribution

It introduces a fully consistent dynamical coupled-channels approach that accounts for multi-channel reaction dynamics and unitarity, providing new insights into nucleon excitations.

Findings

Revealed nucleon excitations as resonant particles from multi-channel dynamics

Demonstrated the importance of unitarity in reaction analysis

Identified features not accessible by static hadron models

Abstract

We review a global analysis of meson production reactions off the nucleons by a collaboration at Excited Baryon Analysis Center of Jefferson Lab. The analysis is pursued with a dynamical coupled-channels approach, within which the dynamics of multi-channel reaction processes are taken into account in a fully consistent way with the two-body as well as three-body unitarity of the S-matrix. With this approach, new features of nucleon excitations are revealed as resonant particles originating from the non-trivial multi-channel reaction dynamics, which cannot be addressed by static hadron models where the nucleon excitations are treated as stable particles.