Coupled-channel contributions to the GDH sum rule from the Jülich-Bonn approach

Abstract

We study the Gerasimov-Drell-Hearn (GDH) sum rule within a dynamical coupled-channel approach, the Jülich-Bonn model for light baryon resonances based on fits to an extensive data base of pion and photon induced data. Recently published photoproduction data for different observables with $\pi N$ and $\eta N$ final states are analyzed simultaneously with older data for the reactions $\pi N\to \pi N$, $\eta N$, $K\Lambda$, $K\Sigma$ and $\gamma p\to \pi N$, $\eta N$, $K\Lambda$, $K\Sigma$. The impact of the new data on the resonance spectrum is investigated and the contribution of the individual channels to the GDH integral is determined.

Comments: 20 pages, 12 figures