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Threshold Behaviour of Meson-Nucleon-$S_{11}$(1535) Vertexfunctions and Determination of the $S_{11}$(1535) Mixing Angle

F. Kleefeld
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Abstract

A new method for the determination of the spin-1/2-3/2-mixing angle and the range parameter of the quarkmodel wavefunction of the resonance $S^-_{11}(1535)$ is presented. The method ist based on a quantitative calculation of the total cross section of $pp\to ppη$ at threshold. The quantitative on-shell treatment of ISI and FSI is discussed.

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F. Kleefeld. 2000-05-14. Threshold Behaviour of Meson-Nucleon-$S_{11}$(1535) Vertexfunctions and Determination of the $S_{11}$(1535) Mixing Angle. https://arxiv.org/abs/nucl-th/9910010

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