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arXiv · 0707.0723

Clustering and Triaxial Deformations of $^{40}$Ca

Yasutaka Taniguchi·Masaaki Kimura·Yoshiko Kanada-En'yo·Hisashi Horiuchi
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Abstract

We have studied the positive-parity states of $^{40}$Ca using antisymmetrized molecular dynamics (AMD) and the generator coordinate method (GCM). Imposing two different kinds of constraints on the variational calculation, we have found various kinds of $^{40}{\rm Ca}$ structures such as a deformed-shell structure, as well as $α$-$^{36}$Ar and $^{12}$C-$^{28}$Si cluster structures. After the GCM calculation, we obtained a normal-deformed band and a superdeformed band together with their side bands associated with triaxial deformation. The calculated $B(E2)$ values agreed well with empirical data. It was also found that the normal-deformed and superdeformed bands have a non-negligible $α$-$^{36}$Ar cluster component and $^{12}$C-$^{28}$Si cluster component, respectively. This leads to the presence of an $α$-$^{36}$Ar higher-nodal band occurring above the normal-deformed band.

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Yasutaka Taniguchi, Masaaki Kimura, Yoshiko Kanada-En'yo, Hisashi Horiuchi. 2007-07-05. Clustering and Triaxial Deformations of $^{40}$Ca. https://doi.org/10.1103/physrevc.76.044317

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