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arXiv · 0704.1594

Cooper pairs in atomic nuclei

G. G. Dussel·S. Pittel·J. Dukelsky·P. Sarriguren
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Abstract

We consider the development of Cooper pairs in a self-consistent Hartree Fock mean field for the even Sm isotopes. Results are presented at the level of a BCS treatment, a number-projected BCS treatment and an exact treatment using the Richardson ansatz. While projected BCS captures much of the pairing correlation energy that is absent from BCS, it still misses a sizable correlation energy, typically of order $1 MeV$. Furthermore, because it does not average over the properties of the fermion pairs, the exact Richardson solution permits a more meaningful definition of the Cooper wave function and of the fraction of pairs that are collective.

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G. G. Dussel, S. Pittel, J. Dukelsky, P. Sarriguren. 2007-04-12. Cooper pairs in atomic nuclei. https://doi.org/10.1103/physrevc.76.011302

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