Coupled-channel dynamics and the Nucleon resonance spectrum

The light baryon resonance spectrum offers a testing ground for theories of the strong force in the non-perturbative energy regime and the last decades have witnessed unprecedented experimental progress in the field. The process of extracting the excited states from those data is a theoretical as well as numerical challenge for which coupled-channel frameworks are especially suited. Here, scattering processes with different initial and final states are analyzed simultaneously, providing a comprehensive picture of the spectrum.
The Juelich-Bonn model is a dynamical coupled-channel approach that aims at including as many constraints from fundamental theory as possible while at the same time making a solid connection to experimental data.
I will present recent results of the Juelich-Bonn analysis of pion-, photon-, and electron-induced reactions and discuss selected resonance states in detail.