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Correlations in Nuclei: Self-Consistent Treatment and the BAGEL Approach

H. Müther·L. D. Skouras
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Abstract

An approach is presented which allows a self-consistent description of the fragmentation of single-particle strength for nucleons in finite nuclei employing the Greens function formalism. The self-energy to be considered in the Dyson equation for the single-particle Greens function contains all terms of first (Hartree-Fock) and second order in the residual interaction. It is demonstrated that the fragmentation of the single-particle strength originating from the terms of second order can efficiently be described in terms of the so-called BAGEL approximation. Employing this approximation the self-energy can be evaluated in a self-consistent way, i.e. the correlations contained in the Greens function are taken into account for the evaluation of the self-energy. As an example this scheme is applied to the nucleus $^{16}O$, using a realistic nucleon nucleon interaction. The effects of the correlations on the occupation probabilities and the binding energy are evaluated.

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H. Müther, L. D. Skouras. 1993-03-29. Correlations in Nuclei: Self-Consistent Treatment and the BAGEL Approach. https://doi.org/10.1016/0370-2693(93)90068-s

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