Prevalence of fission and evaporation in the decay off heavy nuclei excited up to 1000 MeV with energetic antiprotons

Annihilation of 1.2 GeV antiprotons has been explored as a means to generat e high thermal excitation in heavy nuclei (U, Au, Ho) and to observe their decay with:a minimal contribution from dynamical distortion. Conventional f ission and heavy residue formation are found to dominate the decay up to E* approximate to 1000 MeV. Both modes are increasingly accompanied:by a mode st emission of intermediate-mass fragments (up to I on average), but true m ultifragmentation is not observed. These features are in agreement with the predictions of the statistical model with no need for a fission delay iota (f) > 0.5 x 10(-21) s.