Mass drift in reactions between a heavy and a light nucleus

The dynamics of heavy-ion collisions is studied experimentally for metastable composite systems with interaction times between the collision time of quasi- and deep-inelastic processes and the capture time of fast-fission and compound-nucleus-fission reactions. Detailed angular, total kinetic energy and mass distributions are measured for reaction products with masses between the target and projectile masses including the symmetric masses. The mass drift is observed as a function of total kinetic energy and scattering angle.