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Collective Excitations and Ground State Correlations

E. Heinz·H. M"uther·H. A. Mavromatis
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Abstract

A generalized RPA formalism is presented which treats pp and ph correlations on an equal footing. The effect of these correlations on the single-particle Green function is discussed and it is demonstrated that a self-consistent treatment of the single-particle Green function is required to obtain stable solutions. A simple approximation scheme is presented which incorporates for this self-consistency requirement and conserves the number of particles. Results of numerical calculations are given for $^{16}$O using a G-matrix interaction derived from a realistic One-Boson-Exchange potential.

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E. Heinz, H. M"uther, H. A. Mavromatis. 1994-08-18. Collective Excitations and Ground State Correlations. https://doi.org/10.1016/0375-9474(94)00807-y

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