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In-medium Effects in the Eta-Photoproduction through the $S_{11}$ Resonance with the Relativistic Approach

Tomoyuki Maruyama·Satoshi Chiba
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Abstract

In-medium effects in photon excitation of the S$_{11}$ resonance from nucleon and its decay to $η$-meson using the RMF approach is studied. We examine the in-medium effects by varing the Dirac fields of the nucleon and the S$_{11}$ resonance separately. We obtained a conclusion that the Dirac fields of the nucleon, which reduces the nucleon effective mass, enlarge the width of S$_{11}$ resonance, and small Dirac-fields of the resonance shifts the peak position, and these combined effects can explain the in-medium properties observed in the experimental data for $^{12}$C($γ$,$η$) reaction.

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Tomoyuki Maruyama, Satoshi Chiba. 2005-06-07. In-medium Effects in the Eta-Photoproduction through the $S_{11}$ Resonance with the Relativistic Approach. https://doi.org/10.1143/ptp.111.229

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