A Theoretical Study Of The Structure And Properties Of Critical Nuclei In Nuclear Astrophysics

In recent years,due to the application of radioactive nuclear beam and gamma detector in nuclear experiments,it is possible to explore the nuclear structure under extreme conditions.A lot of physical phenomena have been found in the nuclear region far from the stable line,and the study of the nuclear structure far away from the stable line can promote the development of interdiscipline such as nuclear astrophysics.In this paper,the projected shell model is used to study the nuclear structure.At present,one of the frontier topics of nuclear physics is the theoretical study of the key nuclear structure properties in nuclear astrophysics.At the same time,several theoretical models commonly used to describe the properties of deformed nuclei are briefly introduced.It includes collective model,particle rotor model,cranked shell model,mean field theory,density covariant functional theory.Their advantages and disadvantages are discussed.In this paper,the projected shell model is adopted.I know that the traditional shell model is effective in explaining light nuclei,but most nuclei are deformed nuclear chart.In contrast,the projected Nilsson+BCS bases are adopted and the symmetry broken in intrinsic basis is recovered by angular momentum projection.The advantage of the model is that it is suitable to describe even-even,odd-mass and odd-odd nuclei in the same theoretical frame.Furthermore,small configuration space,fast running speed and wide range of application are predominant to other methods.The calculate results can be compared directly with the experimental results and can be used to explain the experimental and provide theoretical predictions.I apply the projected shell model to the neutron-rich nuclear region of A=100-110 far from the stable line and study the nuclear microscopic structure of this region.In this region,we systematically study the nuclei structure of high spin states of ^101,102Sr and ^113-119Ag nuclides.Firstly,the energy levels of yrast band and side bands are discussed,and the energy spectra of nuclides are studied.The theoretical results reproduce the experimental data very well.At the same time,it also predicts more new rotational band which are likely to be detected by experiments.These predictions provides the theoretical basis for further experimental research.Secondly,the moment of inertia and electromagnetic properties?such as B?E2?and g-factor?are studied and compared with the corresponding experimental data.On this basis,the influence of single particle energy level on the microscopic structure of neutron-rich nuclei is further analyzed.Finally,the results show that with the increasing of neutron number,the contribution neutron h_11/21/2 and proton g_9/2 orbitals near the Femi surface plays a major role to the nuclei deformation.The configuration of sideband is mainly constructed by quasi-neutron from N=4 and N=5 shells.For odd-mass nuclei,the single particle configuration excited by them is mainly discussed.Finally,the broad application prospect of projected shell model is summarized and discussed.In this paper,the projected shell model is extended to A=100-110neutron-rich mass region.The experimental results are well reproduced in the theoretical calculation,and theoretical predictions provide valuable information for further experimental research.The projected shell model is applicable to describe the nuclear structure far from the stable linear nucleus.