Nuclear Transitions from Aligned States: Example of Octupole Bands in Actinides

摘要

The changes in the adiabatic picture at I>>1 of the spectrum and of the electromagnetic-transition probabilities are studied theoretically and conclusions are checked with the existing experimental data on negative parity bands in even-even actinides. The model includes the degrees of freedom of the rotating core and of the octupole phonons which are supposed to have fixed values of intrinsic angular-momentum quantum-numbers. It is shown that with the increase of the aligned vibrational angular momentum the selectivity develops in the E3 and E1 transitions from octupole bands to the ground stateband in respect to the amount of angular momentum removed from or added to the nuclear state. The geometrical interpretation of such selectivity is given. The theoretical conclusions are shown to be in a good semiquantitative agreement with the experimental data. (Atomindex citation 13:670820)