Authors: jun he,B.Saghai,Zhenping Li
Title: N* in chiral quark model
Keywords: N*,chiral quark model, missing resonance
Abstract:
Within a chiral constituent quark model approach, eta meson production on the proton via electromagnetic and hadron probes are studied.With few parameters, differential cross-section and polarized beam asymmetry for photoproduction and differential cross section for hadron probes are calculated and successfully compared with the data in the center-of-mass energy range from threshold up to 2 GeV. The five known resonances S11(1535), S11(1650), P13(1720), D13(1520), and F15(1680) are found to be dominant in the reaction mechanism in both channels. Possible roles plaied by new resonances are also investigated and in the photoproduction channel, significant contribution from S11- and D15-resonances, with masses around 1715 MeV and 2090 MeV, respectively, are deduced. The helicity amplitudes and decay widths to pi N and eta N are also presented, and found consistent with the PDG values. |