Research On Sensitivity Of Nuclear Physical Input In R-process And On Superdeformed Nuclear State In Light Mass Region

This paper is divided into two parts:the first part is the study of superdeformed nuclei in A?40 mass region using Particle-Number-Conserving method in Cranked-Shell-Model;the second part is the sensitivity study of various kind of nuclear input in rapid neutron capture process.The study of light superdeformed nuclei using Particle-Number-Conserving method in Cranked-Shell-ModelThe super deformed band has always been a hot topic in the study of nuclear structure,152Dy is super deformed nuclei which is the first experiment found.However,traditional mass regions of super deformed band is A=80,150,190.Over last 15 years,some super deformed band in light nuclei(A=40)have been found experimentally like 36Ar,40Ar,40Ca,these magic or near magic nuclei were spherical at ground state,this exotic shape coexistence phenomenon provide an ideal test ground of theoretical models.The cranked shell model(CSM)with the pairing correlations treated by a particle number conserving(PNC)method has achieved great success in studies of the properties of normal deformed nuclei in A=170 mass region and super deformed nuclei in A= 150,190 mass region,In this work,the CSM-PNC method is used in the super deformed nuclei in A=40 for the first time.The experimental data was reproduced reasonably well by the CSM-PNC method,configurations of these super deformed band and the backbendings mechanics are shown clearly by analyzed by the cranking frequency dependence of the occupation probability of each cranked Nilsson orbital near the Fermi surface and the contributions of orbits from high-j orbits to the angular momentum alignment.These results show that the CSM-PNC method is applicable in this nuclear area and can be used to study the super deformed bands of some heavier nuclei(such as 62Zn).The sensitivity study of various kinds of nuclear input in rapid neutron capture processThe origin of elements has always been a hot topic for scientists.In 1957,Burbidge and others put forward the theory of nuclear synthesis for people to unveil the mysterious veil of elements formation in the universe.About half of nuclide were synthesized by rapid neutron capture process.However,the understanding of fast neutron capture process is very limited,because it is not clear that people can not confirm the astrophysical sites of rapid neutron capture process,and the lack of knowledge about neutron rich nuclide far from the stable line in rapid neutron capture process.Therefore,studying the sensitivity of rapid neutron capture process to the physical properties of these neutron rich nuclei is very meaningful for in-depth understanding of the rapid neutron capture process and determining the locations of the astrophysical sites.In the experiment,we observed the element abundance distribution data of the solar system,and determined the contribution of rapid neutron capture process to the abundance data by physicochemical separation method,which provided a basis for the research of rapid neutron capture process.This paper uses the neutrino driven winds in core collapse supernova as the astrophysical site,uses the experimental data plus calculated values of WS*mass model as the nuclear mass table,because the WS*mass model is the best model on fitting the known nuclear mass by considering the isospin asymmetry and micro mirror nuclei constraint.On this basis,this paper changed a single nuclear input to simulate the rapid neutron capture process,comparing the final theoretical abundance distribution with the experimental data and the baseline,figure out the sensitivity of rapid neutron capture process of nuclear mass,?-decay half life,neutron capture cross section.Which of these three kinds of nuclear inputs are sensitive to nucleus 136Cd only.In addition,in this paper,the influence of the mass of the symmetric energy parameter L and S0 is studied by the WS*mass model,the effect on the rapid neutron capture process is also studied.Furthermore,we expected to study the influence of various physical quantities of single nucleus on the rapid neutron capture process,which is very significant for determining the astrophysical sites where rapid neutron capture occurs.