In-Medium Effects in Eta Photo-production through the S11 Resonance with the Relativistic Approach
نویسندگان
چکیده
In-medium effects in photon excitation of the S11 resonance from a nucleon and its decay into an η-meson are studied using the relativistic mean field approach. We examine the inmedium effects by varying the Dirac fields of the nucleon and the S11 resonance separately. We concluse that the Dirac fields of the nucleon, which reduce the nucleon effective mass, enlarge the width of the S11 resonance, and small Dirac fields of the resonance shift the peak position. These combined effects can account for the in-medium properties observed in the experimental data for C(γ,η) reaction. typeset using PTPTEX.cls 〈Ver.0.9〉
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