The Studies Of Nuclear Force And Excited State Of Nucleon

In the original chiral SU(3)quark model, the nonet pseuo-scalar menson exchanges and the tionet scalar menson exchanges are considered in describing the medium and long range parts of the interations, and the one gluon change exchange (OGE) contributes the short range repulsion. In the extend chairl SU(3) quark model, besides the nonet psedo-scalar menson fields and nonet scalar menson fields, the coupings among vector menson fields with quarks is further considered. By using this extend chairl SU(3) quark model, the phase shifts of NN scattering for different partial waves and the structure of deuteron are studied. The binding energy and corresponding root mean square radius of deuteron are examined. The results show the N-N scattering phase shifts can be reasonably described in this model. Especially the ~1So phase shift can be improved. The results show that the mechanisms for short range interaction in these two models are totally different. In chiral SU(3) quark model, the mechanisms for short range interaction is OGE, and in the extended chiral SU(3) quark model,the mechanisms for short range interaction is vector meson exchange. Considering the 2hw radial excitation, we calculate the. energy of the excited state of nuclon N(1440*). The non-perturbative effects from all chiral fields are investigated. The agreement of N(1440*) with the experiment is improved.