Superdeformed bands in [sup 191]Tl

High spin states in the [sup 191]Tl nucleus have been populated via the [sup 159]Tb ([sup 36]S,4[ital n]) reaction at 165 MeV. Two weakly populated rotational bands have been observed with properties (energy spacings and dynamic moments of inertia) very similar to those of other superdeformed bands in the [ital A][similar to]190 region. The two bands can be interpreted as signature partners which exhibit some signature splitting for rotational frequencies [h bar][omega][ge]0.2 MeV. They are interpreted within the framework of cranked Woods-Saxon calculations as being based on the proton [ital i][sub 13/2]([Omega]=5/2) intruder orbital, in agreement with pairs of superdeformed bands seen in neighboring odd Tl nuclei.