Abstract
Theoretical arguments, based on the pairing-selfconsistent independent quasi-particle model, are presented to support the idea of a collective transition from the superfluid to the normal phase (Mottelson-Valatin effect) in selected actinide nuclei. Detailed calculation results are in good agreement with existing experimental data. The strong relationship between the nucleonic angular momentum alignment and the disappearance of pairing correlations in nuclei is also discussed. It is suggested that a Mottelson-Valatin type mechanism dominates in the excitation pattern of 232-238U, while in the neighbouring thorium and plutonium nuclei the influence of nucleonic alignment and of a band crossing on the high spin properties seems more pronounced.
Export citation and abstract BibTeX RIS