Some Approximations in the Theorie of Moments and Transitions for Even‐Odd Nuclei

Abstract

AbstractIn the framework of Green's functions, the theory of moments and transitions for even‐odd‐nuclei is developed. It is shown, how these quantities are connected with the effective particle‐hole force and the generalized linear response function for the neighbour even‐even nuclei. The response function describes the change of the single‐particle propagator due to an external perturbation. For superfluid systems the Nambu [1] – Engelsberg [2] – Belyaev [3] technique has been used. The connection between earlier treatments is established, especially with the semiphenomenological approach of Migdal [4] and co‐workers. Some approximations for the relevant effective particle‐hole force emerging from the many‐body theory are discussed in detail. Furthermore the generalization of the RPA‐approximation for the auto‐correlation function of density fluctuations in the case of superfluidity is given.