Seminar “Nuclear Theory”
Date and Time: Monday, 24 January 2022, at 3:30 PM
Venue: Blokhintsev lecture hall (4th floor), Bogoliubov Laboratory of Theoretical Physics, online on Zoom
Seminar topic: “Pygmy and giant dipole resonances in neutron-rich nuclei”
Speaker: N. N. Arsenev
Abstract:
The structure of exotic neutron-rich nuclei is one of the main science drivers in
contemporary nuclear physics research. The new measurements of pygmy dipole (PDR) and giant dipole (GDR) resonances in neutron-rich nuclei have stimulated developments of the nuclear models. One of the most popular tool for describing the PDR and GDR is the quasiparticle random phase approximation with the self-consistent mean-field derived from Skyrme effective interactions. Such an approach made it possible to describe the properties of low-lying states and the characteristics of giant multipole resonances in spherical nuclei quite well.
Due to the anharmonicity of vibrations there is a coupling between simple particle-hole configurations and more complex states. As an illustration, westudy the properties of the low-lying dipole states in the neutron-rich Ca, Ni and Sn isotopes. This reveals a number of characteristic features of the low-energy E1 modes. The effect of the low-energy E1 strength on the electric dipole polarizability is discussed. The correlations between the electric dipole polarizability, the symmetry energy, and neutron skin thickness are studied.