Hyperdeformed fission resonances and transition states observed in 232U

Abstract

The fission probability of 232U has been measured using the 231Pa(3He,df) reaction with an energy resolution of 11 keV in the excitation energy region of E* = 4.0 - 6.4 MeV. A number of sub-barrier fission resonances has been observed for the first time in the excitation energy range below E* = 4.8 MeV and interpreted as rotational bands with a rotational parameter characteristic to a hyperdeformed nuclear shape (ℏ2/2Θ = 1.96 ± 0.11 keV). Besides, the fine structure of the transition states could also be resolved in the fission probability and proved to have a rotational structure with a rotational parameter characteristic to a superdeformed-like nuclear configuration (ℏ2/2Θ = 3.25 ± 0.17 keV).