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arXiv · 2312.00750

Shape coexistence and superdeformation in $^{28}$Si

D. Frycz·J. Menéndez·A. Rios·A. M. Romero
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Abstract

We study the shape coexistence of differently deformed states within $^{28}$Si using shell-model and beyond-mean-field techniques. Experimentally, $^{28}$Si exhibits shape coexistence between an oblate ground state and an excited prolate structure. The oblate rotational band is described well within the $sd$ shell using the USDB interaction. However, for the prolate band, a modification of this interaction is required, lowering the single-particle energy of the $1d_{3/2}$ orbit. Furthermore, we explore the possibility of a superdeformed configuration in $^{28}$Si. Our calculations, spanning both the $sd$ and $pf$ shells, rule out the existence of a superdeformed $0^+$ bandhead within an excitation energy range of 10-20 MeV.

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D. Frycz, J. Menéndez, A. Rios, A. M. Romero. 2023-12-01. Shape coexistence and superdeformation in $^{28}$Si. https://doi.org/10.5506/aphyspolbsupp.17.3-a2

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