Pygmy and Giant Dipole Resonances in Proton-Rich Nuclei 17,18Ne**Supported by the National Natural Science Foundation of China under Grant Nos 11375022, 11575060, 11505058 and 11435014.

Abstract

The pygmy and giant dipole resonances in proton-rich nuclei 17,18Ne 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 17,18Ne. 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 17,18Ne, we find that the PDR state is less collective, more like a single 2qp excitation.