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arXiv · 1809.01097

Individual low-energy E1 toroidal and compression states in light nuclei: deformation effect, spectroscopy and interpretation

V. O. Nesterenko·J. Kvasil·A. Repko·P. -G. Reinhard
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Abstract

The existence of individual low-energy E1 toroidal and compression states (TS and CS) in $^{24}$Mg was predicted recently in the framework of quasiparticle random-phase-approximation (QRPA) model with Skyrme forces. It was shown that the strong axial deformation of $^{24}$Mg is crucial to downshift the toroidal strength to the low-energy region and thus make the TS the lowest E1(K=1) dipole state. In this study, we explain this result by simple mean-field arguments. Comparing TS in two strongly axial nuclei, $^{24}$Mg and $^{20}$Ne, we show that the lowest TS is not not a universal phenomenon but rather a peculiarity of $^{24}$Mg. The spectroscopy of TS and CS is analyzed and some additional interpretation of these states is suggested.

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V. O. Nesterenko, J. Kvasil, A. Repko, P. -G. Reinhard. 2018-09-04. Individual low-energy E1 toroidal and compression states in light nuclei: deformation effect, spectroscopy and interpretation. https://doi.org/10.1051/epjconf/201819403005

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