Study Of The Effective Nuclear Force Within Covariant Density Functional Theory

The covariant density functional(CDF)theory,which is based on the meson exchange regime,has achieved great success in describing the properties of nuclear many-body systems.It has become one of the important theoretical platforms for studying the properties of nuclear structure.In the CDF theory,the meson-nucleon coupling constants are generally determined by fitting to the bulk properties of nuclear matter and atomic nuclei,thereby obtaining the so-called effective interaction,which is also called as the effective nuclear force.However,the effective nuclear forces obtained based on different physical considerations have large uncertainties when applied to the study of nuclear structure.In response to this problem,this thesis attempts to build a link between effective nuclear force under the CDF theory and realistic nuclear force.Under the framework of CDF theory,densitydependent meson-nucleon coupling and the contribution of Fock terms are considered.The newly developed realistic nuclear force is used to constrain the effective nuclear force at zero density.A new effective nuclear force is then developed by fitting to the bulk properties of atomic nuclei and nuclear matter,and is also applied to study the nuclear structural properties.The specific content includes the following aspects.Study of Proton Radioactivity within CDF Theory As a test of the effective nuclear force in the CDF theory,the half-lives of the nearly spherical proton emitters are calculated based on the effective interaction DD-ME?.For the first time,the similarity renormalization group method is used to extract the potential barriers that prevents the emitted proton,and naturally gives other relativistic correction terms such as the spin-orbit coupling potential.The half-life calculation employs the WKB approximation and achieves a self-consistent calculation of the spectroscopic factor.The estimated half-lives are found in good agreement with the experimental values,which confirms the validity of the CDF theory in describing the proton-rich nuclei.A New Effective Nuclear Force within CDF Theory Starting from the relativistic oneboson-exchange potential,a new realistic nuclear force LZh1 is built by fitting to the nucleonnucleon scattering phase shift in vacuum and the binding energy of deuteron,in which only ?,?,?,? and ? mesons are considered.The new realistic nuclear force has the same precision as the Bonn potentials on the description of the selected observables.Starting from the zero-density limit assumption,which means the density-dependent meson-nucleon coupling constants at zero density takes the same value as the realistic nuclear force,a new effective nuclear force LZh1-E under CDF theory is developed by fitting to the saturation properties of nuclear matter and the bulk properties of finite nuclei.The new effective interaction can reasonably describe the properties of the selected observables,which supports the assumption of zero density limits.As a test of the new effective interaction LZh1-E,the energy functional,self-energy and equation of state of the nuclear matter,as well as the binding energy,charge density distribution and structure of single-particle energy level of the atomic nuclei,are studied and compared with the existing effective interactions.The new effective interaction LZh1-E describes the above properties of nuclear matter and atomic nuclei with a similar precision as other effective interactions and can eliminate the spurious shell 58 and 92.