Rotational energy and the diffuseness of the boundary between fusion and strongly damped collisions

Differences in the kinetic energies of the fragments produced in the scission of the pairs of similar composite nuclei /sup 59/Cu-/sup 60/Zn and /sup 83/Y-/sup 88/Zr are interpreted as resulting from angular momentum fractionation. The energies indicate that some partial waves with angular momenta 10h to 15h below the sharp-cutoff fusion limit lead to strongly damped collisions.