Relativistic Point Coupling Model for Vibrational Excitations in the Continuum

Abstract

An implementation of the relativistic random phase approximation with the proper treatment of the continuum has been developed for the relativistic point coupling model and applied to investigate collective excitations in spherical nuclei. The results are compared with the spectral implementation of the same model. In heavy nuclei, where the escape width is negligible, we find an excellent agreement between both methods in the region of giant resonance and some discrepancies in the region of low‐lying pygmy resonance. The differences are more pronounced in light nuclei due to the larger values of the escape widths.