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Approximate particle number projection for finite range density dependent forces

A. Valor·J. L. Egido·L. M. Robledo
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Abstract

The Lipkin-Nogami method is generalized to deal with finite range density dependent forces. New expressions are derived and realistic calculations with the Gogny force are performed for the nuclei $^{164}$Er and $^{168}$Er. The sharp phase transition predicted by the mean field approximation is washed out by the Lipkin-Nogami approach; a much better agreement with the experimental data is reached with the new approach than with the Hartree-Fock_Bogoliubov one, specially at high spins.

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A. Valor, J. L. Egido, L. M. Robledo. 1995-05-30. Approximate particle number projection for finite range density dependent forces. https://doi.org/10.1103/physrevc.53.172

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