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arXiv · 1801.10458

The impact of $\mathbf{K^+\Lambda}$ photoproduction on the resonance spectrum

D. Rönchen·M. Döring·U. -G. Meißner
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Abstract

The J\"ulich-Bonn coupled-channel framework is extended to $K^+\Lambda$ photoproduction. The spectrum of nucleon and $\Delta$ 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 40,000 data points up to a center-of-mass energy of E$\sim$2.3 GeV including recently measured double-polarization observables are analyzed. The influence of the $\gamma p\to K^+\Lambda$ channel on the extracted resonance parameters and the appearance of states not seen in other channels is investigated. The J\"ulich-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.

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D. Rönchen, M. Döring, U. -G. Meißner. 2018-01-31. The impact of $\mathbf{K^+\Lambda}$ photoproduction on the resonance spectrum. https://doi.org/10.1140/epja/i2018-12541-3

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