The Microscopic Investigation Of Nuclear Form Factors

The elastic nucleon form factors contain important pieces of information on the internal structure of nucleon and constitute key ingredients to understand the strong interaction. The traditional Relativistic Constituent Quark (RCQ) model appears to be successful in explaining the form factors for the proton, however the calculation results for the neutron have larger difference from the experimental data. So we intent to improve the model through two aspects.First, the effects of SU(6) breaking is investigated . We take the nuclear wave function as followswhere the terms from second to fifth belong to the breaking terms. We have preformed the computation under this wave function. It is shown that the numerical results get better close to experiments. However the fitting of these results to experiments depends on the choice of parameters.Second, the nucleon electromagnetic form factors are also investigated by means of a simple diquark-quark model using the light-front formalism. In this model, baryon is described as a bound state of one quark and one clustering diquark. The calculation results are presented and appear to be improved in the fitting to the experimental ones.The above two methods undergo in parallel for improving the Constituent Quark Model. Although they can interpret the experiment phenomenon in some degree, the further profound studying is required to decide which one the best is.In the final part of this paper, we deal with other facts of nucleon form factors. First, the electromagnetic structure of light front constituent quarks is considered. We find that the calculation results have a good agreement with the new experimental data of GEn and GEn/GMn after considering the contribution of the quark structure term. But this treatment introduces two new parameters ku and kd, and the values of the anomalous magnetic moment need further studying. Second, we discuss the relation between structure functions and form factors in terms of quark-hadron duality. The nucleon's deep-inelasticstructure functions and electromagnetic form factors parameterize fundamental information about its quark substructure. Each of them reflects dynamical behavior of quark wave functions describing the same physical feature, though in different kinematic regions. Some results in the above investigations are given and analysed.