| This paper applies effective Dirac Brueckner Hartree Fock(DBHF) Method, namely, the use of the G matrix decomposition way to solve the nuclear Dirac self-energy calculation,applying the relativistic mean field (RMF) theory to approximatively give scalar self energy and vector self energy that have the same values with DBHF. Then we can get effective interaction coupling constants of isoscalar σ and ω mesons, which are density dependence and contain the short range correlation in the theory of DBHF.Effective DBHF method is microscopic theory for the description of effective interactions in the nuclear medium, the greatest success of this method so directly proceed from the free nucleon-nucleon interaction. In this method, the meson-nucleon coupling constants are no longer constant, but with the change of the nuclear density. The density dependent behavior introduced into the Lagrangian density to study the properties of the finite nuclei. This theory is extended to study the properties of the nucleus far from β stability lines, the results would be more reasonable.In the original literature, effective DBHF calculation only consider the density dependence of the isoscalar σ and ω mesons, while the p meson only calculate by the value of the saturation point. In order to study the isospin dependent behavior of effective interactions, we should be taking into account the density dependence of the isovector meson in the calculation. The article consider the meson density dependence on the basis of the original literature, a systematic study of the influence of isovector meson density dependent behavior on the properties of finite nuclei.Firstly, we rebuild a set of density dependent coupling constants gσ (pB)、 gω (ρB) of σ and ω mesons, so that binding energy per nucleon, charge rms radius closer to the experimental value. On the more reasonable based, the theory increase the density dependent behavior of the ρ meson, through the fixed-pointgρ=2.629fitting a curve, and the binding energy per nucleon and rms radius of the charge are better fitted with the experimental value to determine density dependent coupling constant gσ (ρB) of the p meson.Secondly, with these coupling constants the ground state properties of finite nuclei is given systematically, such as binding energy per nucleon, charge rms radius, two neutron separation energy, proton and neutron1P-1D spin-orbit splitting and proton density distribution. There are three cases, respectively, the coupling constants in the literature[18], the new coupling constants of σ and ω mesons and the coupling constant of p meson on the basis of new coupling constants of σ and ω mesons. We will compare the calculation of properties of finite nuclei in the three cases.Finally, we calculate the properties of isotope chain with these coupling constant, such as the binding energy per nucleon, proton rms radius, neutron rms radius, charge rms radius, two neutron separation energy, protons and neutrons1D spin-orbit splitting and isotope shift, proton and neutron density distribution. And detailed analysis of the results of three cases to discuss the the influence of ρ meson density dependent behavior on the properties of the isotopic chain.The results show that the calculation of the binding energies per nucleon and charge rms radius with the coupling constant of p meson on the basis of new coupling constants of σ and ω mesons are improved, but the degree of improvement is not large compare with coupling constants of σ and ω mesons on the properties of finite nuclei. It conclude that the density dependent behavior of σ and ω mesons play a major role, while the density dependent behavior of ρ meson plays a supporting role. Through the analysis of the calculated values, the influence of ρ meson density dependent behavior on the properties of symmetric nuclear is greater than on the properties of asymmetric nuclear, because ρ meson is isovector meson. Therefore, it is more conducive to the study of the nucleus far from β stability lines. |
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