INTERACTIONS IN HYDROGEN OF RELATIVISTIC NEON TO NICKEL PROJECTILES -TOTAL CHARGE-CHANGING CROSS-SECTIONS

A liquid hydrogen target was used to study the nuclear fragmentation o f beams of relativistic heavy ions, Ne-22 to Ni-58, over an energy ran ge 400 to 900 MeV/nucleon. The experiments were carried out at the Law rence Berkeley Laboratory Bevalac HISS facility, using the charge-velo city-rigidity method to identify the charged fragments. Here we descri be the general concept of the experiment and present total charge-chan ging cross sections obtained from 17 separate runs. These new measured cross sections display an energy dependence which follows semiempiric al model predictions. The mass dependence of the cross sections behave s as predicted by optical models, but within the experimental energy r ange, the optical model parameters display a clear energy dependence. The isospin of the projectile nuclei also appears to be an important f actor in the interaction process.