【摘 要】
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In this report we investigate η-meson productions on the proton via electromagnetic and hadron probes in a chiral quark model approach. The observables, such a
【机 构】
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Institute of Modern Physics,Institut de Recherche sur les lois Fondamentales de l'Univers
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In this report we investigate η-meson productions on the proton via electromagnetic and hadron probes in a chiral quark model approach. The observables, such as, differential cross section and beam asym-metry for the two productions are calculated and compared with the experiment. The five known resonances S_(11)(1535), S_(11)(1650), P_(13)(1720), D_(13)(1520), and F_(15)(1680) are found to be dominant in the reaction mech-anisms in both channels. Significant contribution from a new S_(11) resonances are deduced. For the so-called "missing resonances", no evidence is found within the investigated reactions. The partial wave amplitudes for π~-p→ηn are also presented.
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