Covariant density functional theory and nuclear dynamics far from stability

Abstract

The covariant density functional theory is extended to include the dynamical effects going beyond the scope of the mean field theory. In analogy to the Fermi liquid theory of Landau and Migdal, the theory is based on quasi-particles, which are dressed with a cloud of low-lying collective excitations. These excitations are calculated in a consistent way within the framework of the Relativistic Random Phase Approximation (RRPA). This approach is applied to the study of single particle excitations in odd-mass nuclei, and to a quantitative description of the damping phenomenon in even–even spherical nuclei with closed shells. Since phonon coupling terms enrich the RRPA spectrum with a multitude of ph ⊗ phonon states, a noticeable fragmentation of giant resonance is obtained. The results are compared with experimental data and with results from the non-relativistic approach. We also investigate the influence of particle-vibrational coupling on the recently discovered soft dipole modes in nuclei with large neutron excess.