Nuclear ground state correlations

Abstract

The paper discusses ground state correlations (GSC) in nuclei, which are especially clearly manifested when using the formalism of quantum Green’s functions (FG) and Feynman diagrams. In addition to one-particleone-hole GSC, which appear in the well known random phase approximation method (RPA), there exist and give a noticeable quantitative contribution THE GSCs resulting from the use of configurations that are more complex than in RPA. Namely, configurations containing phonons and configurations containing only three quasiparticles, respectively, the GSC-phon and GSC3. This last case of GSC3 is considered in detail in the present paper. It is shown that GSC3 make a significant quantitative contribution IN THE problems related to the explanation of some characteristics of low-lying excited states (phonons) and transitions between them in even-even nuclei.