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Superdeformation and clustering in $^{40}$Ca studied with Antisymmetrized Molecular Dynamics

Y. Kanada-En'yo·M. Kimura
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Abstract

Deformed states in $^{40}$Ca are investigated with a method of antisymmetrized molecular dynamics. Above the spherical ground state, rotational bands arise from a normal deformation and a superdeformation as well as an oblate deformation. The calculated energy spectra and $E2$ transition strengths in the superdeformed band reasonably agree to the experimental data of the superdeformed band starting from the $0^+_3$ state at 5.213 MeV. By the analysis of single-particle orbits, it is found that the superdeformed state has particle-hole nature of an $8p$-$8h$ configuration. One of new findings is parity asymmetric structure with $^{12}$C+$^{28}$Si-like clustering in the superdeformed band. We predict that $^{12}$C+$^{28}$Si molecular bands may be built above the superdeformed band due to the excitation of inter-cluster motion. They are considered to be higher nodal states of the superdeformed state. We also suggest negative-parity bands caused by the parity asymmetric deformation.

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Y. Kanada-En'yo, M. Kimura. 2005-10-15. Superdeformation and clustering in $^{40}$Ca studied with Antisymmetrized Molecular Dynamics. https://doi.org/10.1103/physrevc.72.064322

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