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arXiv · 2204.00805

Microscopic origin of shape coexistence in the N=90, Z=64 region

Dennis Bonatsos·K. E. Karakatsanis·Andriana Martinou·T. J. Mertzimekis·N. Minkov
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Abstract

A microscopic explanation of the nature of shape coexistence in the N=90, Z=64 region is suggested, based on calculations of single particle energies through standard covariant density functional theory. It is suggested that shape coexistence in the N=90 region is caused by the protons, which create neutron particle-hole (p-h) excitations across the N=112 3-dimensional isotropic harmonic oscillator (3D-HO) magic number, signaling the start of the occupation of the 1i13/2 intruder orbital, which triggers stronger proton-neutron interaction, causing the onset of the deformation and resulting in the shape/phase transition from spherical to deformed nuclei described by the X(5) critical point symmetry. A similar effect is seen in the N=60, Z=40 region, in which p-h excitations across the N=70 3D-HO magic number occur, signaling the start of the occupation of the 1h11/2 intruder orbital.

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Dennis Bonatsos, K. E. Karakatsanis, Andriana Martinou, T. J. Mertzimekis, N. Minkov. 2022-04-02. Microscopic origin of shape coexistence in the N=90, Z=64 region. https://doi.org/10.1016/j.physletb.2022.137099

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