Superdeformed Structures In Pb-197,Pb-198

Two new superdeformed bands, which possess almost constant dynamic moments of inertia as a unction of rotational frequency, have been observed in Pb-197. They are thought to be based upon the favored and unfavored signature components of an N=7 neutron intruder orbital. Previous work tentatively assigned a superdeformed band to Pb-198. The present work has confirmed this assignment. The properties of all the bands are discussed in terms of extended total Routhian surface calculations.