The Studies Of Effect Of Vector Meson Exchange

The extended chiral SU(3) quark model has been proposed to study the different short-range interaction. Based on chiral SU(3) quark model, couplings among vector meson fields with quarks is considered in this extended chiral SU(3) quark model. There are totally different short-range mechanisms in this two models. The OGE is responsible for the short-range mechanism in the chiral SU(3) quark model, and vector meson change effect governs short-range mechanism in the extended chiral SU(3) quark model. In the extended chiral SU(3) quark model, the possible dibaryon candidates are predicted within the framework of resonating group method(RGM). We use the same sets of paramaters which have been successfully employed in the research of N-N scattering phase shifts and deuteron bound state, to study non-strangeness d* and strangeness S=-3 △Ω(S = 3,T = 3/2) dibaryons. The results show, compared to chiral SU(3) quark model, the binding energies of d* and △Ω will be enhanced in the extended chiral SU(3) quark model because the vector meson exchange offer more attractive force to them. However, the prediction of Aft is a weak bound dibaryon state above the threshold of NπΩ. Even though we considet the hidden color channel, the binding energy of d* is still above the threshold of △Nπ, which is very different with the prediction of deeply bound dibaryon state below the threshold of NNππ in other model. In order to test our model, we also give an analysis of the lowest excited states N*(1520) and N*(1535) of nucleon. with negtive parity. The results show, compared to chiral SU(3) quark model, the N*(1520) and N*(1535) states can be better described in the extended chiral SU(3) quark model.