Heavy residue formation in 20 MeV/nucleon 197Au+90Zr collisions Original Research Article

The yields and velocity distributions of heavy residues and fission fragments from the reaction of 20 MeV/nucleon View the MathML source have been measured using the MSU A1200 fragment separator. A bimodal distribution of residues is observed, with one group, resulting from peripheral collisions, having fragment mass numbers A=160–200 while the other group, resulting from “hard” collisions, has A=120–160. These “hard” collision residues can be distinguished from fission fragments by their velocities. A model combining deep-inelastic transfer and incomplete fusion for the primary interaction stage and a statistical evaporation code for the deexcitation stage has been used to describe the properties of the product distributions.