Pygmy and Giant Dipole Resonances in Proton-Rich Nuclei $^{17,18}$Ne
Hong Lv1, Shi-Sheng Zhang2, Zhen-Hua Zhang1, Yu-Qian Wu1, Li-Gang Cao1**
1School of Mathematics and Physics, North China Electric Power University, Beijing 102206 2School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191
Abstract：The pygmy and giant dipole resonances in proton-rich nuclei $^{17,18}$Ne are investigated with a fully self-consistent approach. The properties of ground states are calculated in the Skyrme Hartree–Fock with the Bardeen–Cooper–Schrieffer approximation to take into account the pairing correlation. The quasiparticle random phase approximation (QRPA) method is used to explore the properties of excited dipole states. In the calculations the SLy5 Skyrme interaction is employed. In addition to the giant dipole resonances, pygmy dipole resonances (PDR) are found to be located in the energy region below 10 MeV in both $^{17,18}$Ne. The strength and transition density show that the low-lying states are typical PDR states. However, analyzing the QRPA amplitudes of proton and neutron 2 quasiparticle (2qp) configurations for a given low-lying state in $^{17,18}$Ne, we find that the PDR state is less collective, more like a single 2qp excitation.
2017, Vol. 34 
