SUPERDEFORMED NUCLEI

The discovery of rotational bands associated with superdeformed shapes was linked with developments in gamma-ray instrumentation. These developments have continued and the EUROGAM I array has improved the observational limit by an order of magnitude. Many excited bands in the A = 150 region have been found and their properties show their particle-hole nature, the importance of high-N orbital occupation and the influence of pairing correlations at high spin. Data on the decay-out from the bands indicates the major factor initiating the de-excitation is the high-N configuration. There is evidence of fourfold symmetry from a DELTAI = 4 staggering of energy levels in the yrast superdeformed band of Gd-149. Further planned developments in instrumentation will enhance the prospects for new discoveries.