New shape minimum in $^{160}$Yb: Evidence for a triaxial, strongly deformed band
A. Aguilar, D. B. Campbell, K. Chandler, A. Pipidis, M. A. Riley, C. Teal, J. Simpson, D. J. Hartley, F. G. Kondev, R. M. Clark, M. Cromaz, P. Fallon, I. Y. Lee, A. O. Macchiavelli, and I. Ragnarsson

A high-spin rotational band has been observed in the N=90 nucleus $^{160}$Yb with moment of inertia and decay characteristics very similar to recently discovered sequences in $^{157,158}$Er. These latter structures have been discussed in terms of strongly deformed triaxial bands. Detailed cranked Nilsson-Strutinsky calculations have been performed which predict that well-deformed triaxial structures are also expected at high-spin in $^{160}$Yb. Within this interpretation the observed discontinuity in the dynamic moment of inertia around $\hbar \omega = 0.40-0.45$ MeV can be explained as a crossing between $i_{13/2}$ neutron levels.

© 2008 The American Physical Society.