Investigation of single-particle core-excitation coupling in the strontium and lead regions

Abstract

The nuclei neighbouring 88Sr and 208Pb are treated as a core plus an additional particle or hole interacting with the core vibrations. With the help of the Green function technique the core vibrations are described as collective particle-hole excitations thus depending on the single-particle propagators. An iterative calculation has been performed for 88Sr, showing that the coupling of single-particle and collective modes is very important. Because of angular momentum coupling and parity selection rules the coupling possibilities are strongly reduced in the lead region.