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Barrier penetration and rotational damping of thermally excited superdeformed nuclei

K. Yoshida·M. Matsuo·Y. R. Shimizu
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Abstract

We construct a microscopic model of thermally excited superdeformed states that describes both the barrier penetration mechanism, leading to the decay-out transitions to normal deformed states, and the rotational damping causing fragmentation of rotational E2 transitions. We describe the barrier penetration by means of a tunneling path in the two-dimensional deformation energy surface, which is calculated with the cranked Nilsson-Strutinsky model. The individual excited superdeformed states and associated E2 transition strengths are calculated by the shell model diagonalization of the many-particle many-hole excitations interacting with the delta-type residual two-body force. The effect of the decay-out on the excited superdeformed states are discussed in detail for $^{152}$Dy, $^{143}$Eu and $^{192}$Hg.

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K. Yoshida, M. Matsuo, Y. R. Shimizu. 2000-10-23. Barrier penetration and rotational damping of thermally excited superdeformed nuclei. https://doi.org/10.1016/s0375-9474(01)01123-x

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