Relation of E1 pygmy and toroidal resonances

Abstract

A possible relation of the low-lying E1 (pygmy resonance) and toroidal strengths is analyzed by using Skyrme-RPA results for the strength functions, transition densities and current fields in ${}^{208}$Pb. It is shown that the irrotational pygmy motion can appear as a local manifestation of the collective vortical toroidal dipole resonance (TDR) at the nuclear surface. The RPA results are compared to unperturbed (1ph) ones.

Comments: 3 pages, 5 figures, to be submitted to EPJ Web of Conferences [Proceedings of 15th International Symposium on Capture Gamma-Ray Spectroscopy and Related Topics (CGS15), Dresden, Germany, August 24-29, 2014]