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A coupled-channel analysis of $KΛ$ production in the nucleon resonance region

V. Shklyar·H. Lenske·U. Mosel
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Abstract

A unitary coupled-channel effective Lagrangian model is applied to the combined analysis of the $(π,γ) N \to KΛ$ reactions in the energy region up to 2 GeV. To constrain the resonance couplings to the $KΛ$ final state the recent photoproduction data obtained by the SAPHIR, SPring-8, and CLAS groups are included into the calculations. The main resonance contributions to the process stem from the $S_{11}(1650)$, $P_{13}(1720)$, and $P_{13}(1900)$ states. The second bump at 1.9 GeV seen in the photoproduction cross section data is described as a coherent sum of the resonance and background contributions. The prediction for the beam polarization observable is presented.

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V. Shklyar, H. Lenske, U. Mosel. 2005-05-03. A coupled-channel analysis of $KΛ$ production in the nucleon resonance region. https://doi.org/10.1103/physrevc.72.015210

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