Fragmentation ofAu197by 21 MeV/nucleonXe129

Abstract

We have measured the nuclidic production cross sections and recoil properties for intermediate mass fragments, fission fragments, and heavy residues from the interaction of 21 MeV/nucleon $^{129}\mathrm{Xe}$ with $^{197}\mathrm{Au}$. From these measurements, we have deduced the fragment mass distributions and fragment velocities, momenta, etc. The fragment N/Z ratios, isomeric state populations, and mean fragment energies are similar to those observed in low energy, deep inelastic scattering. The stochastic nucleon exchange model correctly predicts the shape of the heavy residue mass distribution, but overestimates (by a factor of 2--3) the fragment longitudinal velocities as does the dissipative fragmentation model, perhaps due to the lack of preequilibrium emission in these models.