The impact of K+ Λ photoproduction on the resonance spectrum

The Julich-Bonn coupled-channel framework is extended to K+ Lambda photoproduction. The spectrum of nucleon and. resonances is extracted from simultaneous fits to several pion-induced reactions in addition to pion, eta and K+ Lambda photoproduction off the proton. More than 40000 data points up to a center-of-mass energy of E similar to 2.3 GeV including recently measured double-polarization observables are analyzed. The influence of the gamma p -> K+ Lambda channel on the extracted resonance parameters an Julich-Bonn model includes effective three-body channels and guarantees unitarity and analyticity, which is a prerequisite for a reliable determination of the resonance spectrum in terms of poles and residues.