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The eta Photoproduction of Nucleons and The structure of the Resonance S11(1535) in The Quark Model

Zhenping Li
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Abstract

In this paper, we present our study on the $η$ photoproduction based on the chiral quark model. We find that quark model provides a very good description of the $η$ production with much less parameters, and the threshold region is not a reliable source to determine the $ηNN$ coupling constant due to its strong dependence on the properties of the resonance $S_{11}(1535)$. We suggest that the systematic data in $E_{lab}=1.2 \sim 1.4$ GeV region may help us to determine the $ηNN$ coupling constant more precisely. The structure of the resonance $S_{11}(1535)$ is discussed, we find that the recent data from Mainz group bring the helicity amplitude much closer to the quark model prediction. However, more studies need to be done to understand the large $ηN$ branching ratio of the resonance $S_{11}(1535)$. Our results show that the quark model is a very good approach to study the underlying structure of baryon resonances from the meson photoproduction data.

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Zhenping Li. 1995-06-30. The eta Photoproduction of Nucleons and The structure of the Resonance S11(1535) in The Quark Model. https://doi.org/10.1103/physrevd.52.4961

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