The 174Yb(29Si,5n) reaction at 148 MeV with thin targets was used
to populate high-angular momentum states in 198Po. Resulting γ rays
were observed with Gammasphere. A weakly-populated superdeformed band of 10
γ-ray transitions was found and has been assigned to 198Po. This is
the first observation of a SD band in the A≈190 region in a nucleus
with Z>83. The J(2) of the new band is very similar to those of
the yrast SD bands in 194Hg and 196Pb. The intensity profile suggests
that this band is populated through states close to where the SD band crosses
the yrast line and the angular momentum at which the fission process dominates.Comment: 10 pages, revtex, 2 figs. available on request, submitted to Phys.
Rev. C. (Rapid Communications