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arXiv · 1404.5226

Isovector proton-neutron pairing and Wigner energy in Hartree-Fock mean field calculations

D. Negrea·N. Sandulescu
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Abstract

We propose a new approach for the treatment of isovector pairing in self-consistent mean field calculations which conserves exactly the isospin and the particle number in the pairing channel. The mean field is generated by a Skyrme-HF functional while the isovector pairing correlations are described in terms of quartets formed by two neutrons and two protons coupled to the total isospin T=0. In this framework we analyse the contribution of isovector pairing to the symmetry and Wigner energies. It is shown that the isovector pairing provides a good description of the Wigner energy, which is not the case for the mean field calculations in which the isovector pairing is treated by BCS-like models.

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D. Negrea, N. Sandulescu. 2014-04-21. Isovector proton-neutron pairing and Wigner energy in Hartree-Fock mean field calculations. https://doi.org/10.1103/physrevc.90.024322

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