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

D. Vretenar, N. Paar, P. Ring, G. A. Lalazissis

Published 2001-01-29Version 1

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.