SOME NEW ASPECTS OF NUCLEAR-STRUCTURE AT HIGH SPINS

This paper will focus on the properties of lead and some neighboring nuclei at high spins where they have exotic shapes, such as superdeformed (SD) and oblate. The limits of the region of superdeformation around mass 190 will be explored. On the heavy side, the lead nuclei form the high-Z limit. On the light side, a new SD band has been observed in 191Au, the first one in a gold nucleus, extending the low-Z limit. Collective oblate bands, not often found in the nuclear chart, have recently been observed in a number of lead nuclei (and also in Tl and Hg nuclei) at high spins. They are favored because the Fermi level is located near the oblate-driving high-K h9/2 and i13/2 proton orbitals. Their properties will be examined. A summary of what we hope to learn in the near future will conclude this paper.