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arXiv · 2212.05940

Islands of shape coexistence: theoretical predictions and experimental evidence

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

Parameter-free theoretical predictions based on a dual shell mechanism within the proxy-SU(3) symmetry of atomic nuclei, as well as covariant density functional theory calculations using the DDME2 functional indicate that shape coexistence (SC) based on the particle-hole excitation mechanism cannot occur everywhere on the nuclear chart, but is restricted on islands lying within regions of 7-8, 17-20, 34-40, 59-70, 96-112, 146-168 protons or neutrons. Systematics of data for even-even nuclei possessing K=0 (beta) and K=2 (gamma) bands support the existence of these islands, on which shape coexistence appears whenever the K=0 bandhead 0_2^+ and the first excited state of the ground state band 2_1^+ lie close in energy, with nuclei characterized by 0_2^+ lying below the 2_1^+ found in the center of these islands. In addition a simple theoretical mechanism leading to multiple shape coexistence is briefly discussed.

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Andriana Martinou, Dennis Bonatsos, S. K. Peroulis, K. E. Karakatsanis, T. J. Mertzimekis, N. Minkov. 2022-12-12. Islands of shape coexistence: theoretical predictions and experimental evidence. https://doi.org/10.3390/sym15010029

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