Barrier penetration and rotational damping of thermally excited superdeformed nuclei

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.

Comments: 33pages, 32 figures, submitted to Nucl.Phys.A