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arXiv · 2207.06201

Anomalous low-energy $E2$-related behavior in triaxial nuclei

Yu Zhang·Ying-Wen He·D. Karlsson·Chong Qi·Feng Pan·J. P. Draayer
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Abstract

The anomalous low-energy $E2$-related behavior of a triaxially-deformed nucleus bas been identified and analyzed based on the SU(3) algebraic theory within the framework of the interacting boson model. The results show striking features that include a $B(E2;4_1^+\rightarrow2_1^+)/B(2_1^+\rightarrow0_1^+)<1.0$ transition rate ratio and a $E(4_1^+)/E(2_1^+)>2.0$ excitation energy ratio that can be tracked back to a finite-$N$ effect, which in a large-$N$ limit of the theory yields normal results for a stable $\gamma$-deformation. This description is shown to be able to explain observed $E2$ anomalous phenomenon in neutron-deficient nuclei such as $^{172}$Pt and $^{168}$Os, and in so doing yields a deeper understanding of the physical features of a soft triaxially-deformed nucleus.

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Yu Zhang, Ying-Wen He, D. Karlsson, Chong Qi, Feng Pan, J. P. Draayer. 2022-07-13. Anomalous low-energy $E2$-related behavior in triaxial nuclei. https://doi.org/10.1016/j.physletb.2022.137443

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