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arXiv · 1003.5720

Shell structure in neutron-rich Ca and Ni nuclei under semi-realistic mean fields

H. Nakada
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Abstract

Shell structure in the neutron-rich Ca and Ni nuclei is investigated by the spherical Hartree-Fock calculations with the semi-realistic $NN$ interactions. Specific ingredients of the effective interaction, particularly the tensor force, often play a key role in the $Z$ dependence of the neutron shell structure. Such examples are found in N=32 and N=40; N=32 becomes magic or submagic in $^{52}$Ca while its magicity is broken in $^{60}$Ni, and N=40 is submagic (though not magic) in $^{68}$Ni but not in $^{60}$Ca. Comments are given on the doubly magic nature of $^{78}$Ni. We point out that the loose binding can lead to a submagic number N=58 in $^{86}$Ni, assisted by the weak pair coupling.

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H. Nakada. 2010-05-07. Shell structure in neutron-rich Ca and Ni nuclei under semi-realistic mean fields. https://doi.org/10.1103/physrevc.81.051302

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