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arXiv · 1601.05598

Isoscalar-isovector proton-neutron pairing and quartet condensation in N=Z nuclei

M. Sambataro·N. Sandulescu
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Abstract

We show that the correlations generated in the ground state of $N=Z$ nuclei by the isovector and isoscalar pairing forces can be treated with high precision as a condensate of alpha-like quartets. To treat these correlations, the quartet condensation model (QCM) is extended to the treatment of spherically symmetric isovector $(T=1,J=0)$ and isoscalar $(T=0,J=1)$ pairing forces . Within QCM we discuss the competition between $T=1$ and $T=0$ pairing correlations in the case of a two-level model and for $N=Z$ nuclei with nucleons moving in the open shells above $^{16}$O, $^{40}$Ca and $^{100}$Sn. We show that in $N=Z$ systems isovector and isoscalar proton-neutron pairing correlations always coexist.

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M. Sambataro, N. Sandulescu. 2016-01-21. Isoscalar-isovector proton-neutron pairing and quartet condensation in N=Z nuclei. https://doi.org/10.1103/physrevc.93.054320

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