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arXiv · 2305.17550

Signatures for shape coexistence and shape/phase transitions in even-even nuclei

Dennis Bonatsos·Andriana Martinou·S. K. Peroulis·T. J. Mertzimekis·N. Minkov
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Abstract

Systematics of B(E2) transition rates connecting the first excited 0+ state to the first excited 2+ state of the ground state band in even-even nuclei indicates that shape coexistence of the ground state band and the first excited K=0 band should be expected in nuclei lying within the stripes of nucleon numbers 7-8, 17-20, 34-40, 59-70, 96-112 predicted by the dual shell mechanism of the proxy-SU(3) model, avoiding their junctions, within which high deformation is expected. Systematics of the excitation energies of the first excited 0+ states in even-even nuclei show that shape coexistence due to proton-induced neutron particle-hole excitations is related to a first-order shape/phase transition from spherical to deformed shapes, while shape coexistence due to neutron-induced proton particle-hole excitations is observed along major proton shell closures.

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Dennis Bonatsos, Andriana Martinou, S. K. Peroulis, T. J. Mertzimekis, N. Minkov. 2023-05-27. Signatures for shape coexistence and shape/phase transitions in even-even nuclei. https://doi.org/10.1088/1361-6471%2Facd70b

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