Superdeformation in Pb198, 196

A weakly populated rotational band with energy spacings characteristic of superdeformation has been found in the reaction Sm154(48Ca, xn) at E(48Ca)=205 MeV. This band has seven transitions with an average -ray energy spacing of approximately 42 keV. It is assigned to Pb198 on the basis of the excitation-function results. We also confirm the isotopic assignment of a previously reported superdeformed (SD) band in Pb196 via the cross bombardments Yb176(26Mg, xn) and Yb176(24Mg, xn). Three SD bands have now been identified in the Pb isotopes with neutron numbers 112, 114, and 116.