Abstract
We present a version of the random-phase approximation for the description of nuclear excitations which is a consistent extension of the QHD1 mean-field theory of the ground states of doubly magic nuclei. This approach includes correlations induced by the isoscalar σ and ω mesons of QHD1. Our method employs a nonspectral single particle propagator in such a way that we avoid any basis truncation and automatically include the escape widths implied by the theory. Our calculations yield exactly conserved random-phase approximation transition currents as well as correct treatment of spuriosity for T=0 excitations. Because of the flexibility of our numerical method, we can treat discrete excitations, giant resonances, and the continuum response in general—including quasielastic scattering—in a unified way. We compare our results with experimental (e,e’) form factors for various discrete excitations in , , , and as well as with the quasielastic Coulomb response functions for and . Agreement with transition charge densities is typically quite good and in some cases superior to comparable nonrelativistic random-phase approximation calculations. Transition current densities are less well described. The question of sum rules in the relativistic random-phase approximation is also addressed.
- Received 18 January 1989
DOI:https://doi.org/10.1103/PhysRevC.40.2320
©1989 American Physical Society