Multiple scattering equation for two particle-one hole system and generalized vertex in core polarization of nuclei, 1

A multiple-scattering equation for a two particle-one hole system is presented to give generalized vertices causing core-polarization. In this equation full exchanges and full interactions among the 2p1h are taken into account. Equivalency with a shell model approach is proved. Effective one-body operators and effective two-body interactions are expressed in terms of those vertices. A discussion is made of how the approximated treatments such as Kirson's vertex-modification are derived. Illustrative calculations are carried out to get qualitative understanding. (auth.)