Collectivity of the low-lying dipole strength in relativistic random phase approximation

Abstract

The relativistic random phase approximation is applied in the analysis of the evolution of the isovector dipole response in nuclei with a large neutron excess. The self-consistent framework of relativistic mean-field theory, which has been very successfully applied in the description of ground-state properties of nuclei far from the valley of $\beta$-stability, is extended to study the possible onset of low-energy collective isovector dipole modes in nuclei with extreme isospin values.

Comments: 29 pages LaTeX, 14 eps figs, to appear in Nucl. Phys. A