Abstract
High-spin states in have been studied experimentally using the (, ) reaction at beam energies of 78 and 85 MeV. The previously known bands based on the , and configurations have been extended to high-spin states, and new rotational bands associated with the and Nilsson orbits have been identified. The total Routhian surface calculations indicate that the transitional nucleus is very soft with respect to and deformations. The band properties, such as level spacings, band crossing frequencies, alignment gains, and signature splittings, have been compared with the systematics observed in neighboring nuclei and have been interpreted within the framework of the cranked shell model. The rotational bands show different band crossing frequencies, which can be explained by the alignment either of neutrons or of protons. Importantly, evidence is presented for a alignment at very low frequency in the band. The proton nature of the band crossing is strongly suggested by comparing the measured ratios with the theoretical values from the semiclassical Dönau and Frauendof approach.
6 More- Received 11 December 2006
DOI:https://doi.org/10.1103/PhysRevC.75.034314
©2007 American Physical Society