Skyrme-Rpa Description of Dipole Giant Resonance in Heavy and Superheavy Nuclei

TL;DR

This paper uses a self-consistent Skyrme RPA model to analyze the dipole giant resonance in heavy and superheavy nuclei, successfully reproducing experimental data and exploring the effects of deformation and mode mixing on resonance properties.

Contribution

It applies a self-consistent separable RPA approach with Skyrme SLy6 to systematically study GDR in a broad range of heavy nuclei, including superheavy elements, highlighting deformation effects.

Findings

The model accurately reproduces experimental energies and widths.

Resonance peak energies follow collective model estimates, with mode bias depending on nucleus type.

Deformation significantly influences GDR width and splitting.

Abstract

The E1(T=1) isovector dipole giant resonance (GDR) in heavy and super-heavy deformed nuclei is analyzed over a sample of 18 rare-earth nuclei, 4 actinides and three chains of super-heavy elements (Z=102, 114 and 120). Basis of the description is self-consistent separable RPA (SRPA) using the Skyrme force SLy6. The self-consistent model well reproduces the experimental data (energies and widths) in the rare-earth and actinide region. The trend of the resonance peak energies follows the estimates from collective models, showing a bias to the volume mode for the rare-earths isotopes and a mix of volume and surface modes for actinides and super-heavy elements. The widths of the GDR are mainly determined by the Landau fragmentation which in turn is found to be strongly influenced by deformation. A deformation splitting of the GDR can contribute about one third to the width and about 1 MeV further broadening can be associated to mechanism beyond the mean-field description (escape, coupling with complex configurations).