The Research Of Treating The Pairing Correlation In Nucleus

In this thesis,we have introduced several important nuclear structure models including the relativistic mean field theory (RMF) and their description on the spherical and deformed nuclei. We have introduced the method for the pairing correlation, and discussed the knowledge of pairing correlation and their correlation with these models. This paper mainly summarized as follows:Chapter Ⅰ,we have reviewed four kinds of nonrelativistic models, including the liquid drop model, fermi gas model, shell model and collective model. Although these four models are proposed in the nonrelativistic theory, but all of them have successfully described the atomic nucleus in some areas. The liquid drop model can give a reasonable explanation of mass rules in nuclear physics. Fermi gas model can give a good explanation for the symmetry energy. Shell model can well explain the magic number. On the basis of shell model, the collective motion and nuclear deformation is proposed, it also gives a good explanation for the nucleus far away from magic number. All of them absorbed the advantage of former models and developed based on them. Fermi gas model also can explain mass rules. Shell model can describe symmetric energy too. Collective model can launched the magic number. With the appearance of different models, their scope of application is more and more wide. Shell model is accurate if nucleon number is magic number or nearby. The scope of collective model can be extended to the situation far away from the magic nuclei. With the development of nuclear physics, the nucleon far away from β stability line has been paid more and more people’s attention and research. It requires quantum field theory to deal with the problem based on relativistic effect, then we will introduce the relativistic mean field theory.Chapter Ⅱ, we described the relativistic mean field theory in detail. Putting the Lagrangian including nuclear, mesons and photons into Euler-Lagrange equation, we can obtain Dirac equation, Klein-Gordon and the electromagnetic field equation of photon. Then we showed the form of them for spherical nucleus and deformed nuclei.Chapter III, the concept of pairing correlation and several models dealing with it are given. The process of pairing interconnection and δ force is given.δ force is simple, but calculation and analysis about it are still very complicated. So we suppose there exist a pairing force between two nucleus. The following presents two methods of dealing with pairing force-BCS approximation and Shell-Model-Like Approach (SLAP).Chapter IV, by comparing the graphs from BCS method with that from SLAP method, we obtained that the curve of SLAP is close to curve of BCS if Ec is large enough. Both of them can be used to deal with pairing correlation.We have researched the isotopes of oxygen by use BCS approximation in frame of RMF theory. The results from RMF+BCS method are consistent with experimental data.