Alignments in the odd-proton actinides 237 Np and 241 Am
Abstract
High spin states in 237 Np and 241 Am have been studied with the “unsafe” Coulomb excitation technique. In each nucleus, signature partner rotational bands built on the [523]5/ 2- and [642]5/ 2+ orbitals of respective h9/2 and i13/2 parentage have been delineated. An additional pair of bands based on the [521]3/ 2- ( f7/2 ) state was also observed in 241 Am . New information on the even-even 236 Pu and 242 Cm transfer products is also presented. From the present data, the role of i13/2 protons in generating angular momentum in the even-even nuclei of the region is documented. A satisfactory description of the evolution of the rotational sequences with spin is achieved within the framework of the cranked shell model. Nevertheless, when combined with information on odd-neutron nuclei available from elsewhere, the data highlight significant shortcomings of the available theoretical predictions.
- Publication:
-
Physical Review C
- Pub Date:
- August 2004
- DOI:
- 10.1103/PhysRevC.70.024310
- Bibcode:
- 2004PhRvC..70b4310A
- Keywords:
-
- 27.90.+b;
- 23.20.Lv;
- 21.10.Re;
- 21.60.Ev;
- 220<
- =A;
- gamma transitions and level energies;
- Collective levels;
- Collective models