Study of static and dynamic properties of even-even ^14–24O and ^38–54Ca in the frame of Random Phase Approximation (RPA) method with different Skyrme parameterizations

Abstract

The static and dynamic nuclear properties for neutron rich oxygen and calcium isotopes have been calculated using the framework of the random phase approximation method with different Skyrme parameterizations namely; SyO-, SyO+, BSk17, SLy4, SLy5, and SkX. The nuclear charge radii, the binding energy per nucleon were calculated and compared to the experimental one to choose the best Skyrme interactions used in the calculations of dynamic properties. The two-neutron separation energy for isotopes under study has been calculated and compared to experimental data. Higher modes of the excited states, energy-weighted sum rule, the centroid, constrained, and scaling energies of the resonances have been studied and illustrated together with available experimental data for comparison. For the low-lying excited states, the energy transition densities for J π = 2+ and J π = 3− are reproduced well in 18–24O and 46–54Ca isotopes. The neutron single particle states as a function of neutron number have been also presented. The results show that the random phase approximation calculations with Skyrme-type interactions is a successful method for describing nuclear structure properties of neutron rich nuclei near the drip line.

Study of the Nuclear Structure for Some Nuclei Using Self-Consistent RPA Calculations with Skyrme-Type Interaction

“…For collective electric excitations, the transition density is useful for the low-lying excited states for nuclei 58 Ni, 90 Zr, 116 Sn and 144 Sm, The radial transition densities of protons and neutrons for the RPA state are shown in Figs. (5)(6)(7)(8)(9)(10)(11)(12). Compared to the existing experimental data, the estimated excitation energy of the negative parity excited states is qualitatively consistent with the results of the experiments ( 90 Zr has state 3 -(2.747875MeV), 116 Sn has states 3 -(2.66159MeV) and 7 -(2.90885MeV), and 144 Sm has state 5 -(2.82517MeV)).…”

“…The nuclear shell model is based on the premise that each nucleon (proton or neutron) travels in the average field independently to the first order. RPA based on Hartree-Fock (HF) has been particularly successful in describing collective motion phenomena in nuclei at the microscopic level [6]. The HF and RPA nuclear structure approaches are widely regarded as highly successful in designing the ground states and excitations of spherical nuclei with effective interactions that are density-dependent [7].…”