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DOE OSTI · 1864860

Rotational bands beyond the Elliott model

Zbikowski, Ryan·Johnson, Calvin W.·McCoy, Anna E.·Caprio, Mark A.·Fasano, Patrick J.
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Abstract

Rotational bands are commonplace in the spectra of atomic nuclei. Inspired by early descriptions of these bands by quadrupole deformations of a liquid drop, Elliott constructed discrete nucleon representations of SU(3) from fermionic creation and annihilation operators. Ever since, Elliott's model has been foundational to descriptions of rotation in nuclei. Later work, however, suggested the symplectic extension Sp(3, R) provides a more unified picture. We decompose no-core shell-model nuclear wave functions into symmetry-defined subspaces for several beryllium isotopes, as well as 20 Ne, using the quadratic Casimirs of both Elliott's SU(3) and Sp(3, R). The band structure, delineated by strong B(E2) values, has a more consistent description in Sp(3, R) rather than SU(3). In particular, we confirm previous work finding in some nuclides strongly connected upper and lower bands with the same underlying symplectic structure.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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Zbikowski, Ryan, Johnson, Calvin W., McCoy, Anna E., Caprio, Mark A., Fasano, Patrick J.. 2021-05-19. Rotational bands beyond the Elliott model. https://doi.org/10.1088/1361-6471%2Fabdd8e

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