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In the fusion-fission reaction {sup 40}Ar+{sup 116}Cd{r_arrow}{sup 156}Dy{r_arrow}fission, performed at beam energies {ital E}{sub {ital b}}=216 MeV and 238 MeV, {gamma} rays were measured in coincidence with fission fragments. The {gamma}-ray spectra are interpreted using a modified version of the statistical-model code CASCADE. From a comparison of the experimental and calculated spectra it is deduced that the nuclear viscosity is in the range 0.01{lt}{gamma}{lt}4. The extracted fission time scale is of the order of 10{sup {minus}19} s. {copyright} {ital 1996 The American Physical Society.}

An experiment was performed to measure the lifetimes of the states in the superdeformed band reported in $^{192}\mathrm{Pb}$. No evidence for such a band was found, despite the fact that the experimental conditions were nearly identical to those of an earlier measurement where this band was proposed. The problems and questions encountered in the analysis are described. The arguments presented here indicate that further measurements are needed to establish the existence of a superdeformed band in this nucleus unambiguously.