Light baryon resonances from a coupled-channel study including $\mathbf{K\Sigma }$ photoproduction

Abstract

The Jülich-Bonn dynamical coupled-channel approach is extended to include $K\Sigma$ photoproduction off the proton. Differential cross section and (double) polarization data for $K^{+}{\Sigma }^0$ and $K^0{\Sigma }^{+}$ are analysed simultaneously with the pion- and photon-induced production of $\pi N$, $\eta N$, $K\Lambda$, and $K\Sigma$ final states, totaling more than 67,000 data points for center-of-mass energies $W<2.4$ GeV. Based on the fit results the spectrum of $N^{\ast }$ and $\Delta$ resonances is extracted in terms of pole positions and residues. We discuss the impact of the $\gamma p\to K\Sigma$ channels in detail and investigate the influence of recent polarization data for $\eta p$ photoproduction.

Comments: Updated to the published version