PYGMY DIPOLE RESONANCE AND TWO NEUTRON SEPARATION ENERGIES IN SOFT AND HEAVY NUCLEI

Abstract

We investigate isovector pygmy dipole resonance (IVPDR) for the case of neutron-rich soft nuclei 68 Ni , and heavy nuclei such as 112 Sn and 208 Pb using effective nucleon–nucleon Skyrme interaction. We use the mean-field theory and employ the random phase approximation (RPA). We observe that our results for the pygmy dipole resonance (PDR) for neutron-rich nuclei are in reasonable agreement with their experimental results. We also predict PDR for very neutron-rich heavy nuclei. We then study two-neutron separation Skyrme energies (S2n) using the Hartree–Fock + BCS with and without tensor interaction in the same nucleus and compare our results with their experimental values. We see that the total binding energies of nuclei 208 Pb are not extremely sensitive to the tensor interaction.