Fission time scales from anisotropic in-plane distributions inMo100+100Mo andSn120+120Sn collisions around 20AMeV

The characteristics of the fission step following a binary deep-inelastic interaction have been reconstructed for three-body events detected in the reaction ${}_{}{}^{100}{}_{}{}^{}\mathrm{Mo}$ ${+}^{100}$Mo at 18.7A MeV and ${}_{}{}^{12\mathrm{-}}{}_{}{}^{}\mathrm{Sn}$ ${+}^{120}$Sn at 18.4A MeV. The observed anisotropy of the in-plane angular distributions points to the fast decay of a rotating (and strongly deformed) nuclear object formed at the end of the deep-inelastic interaction. The derived time scale of the process indicates that asymmetric divisions are faster than symmetric ones.