Multiple Ionization And Collision Dynamics In High-energy Uranium-rare Gas Collisions

The multiple ionization of rare gas target atoms in collisions with MeV/u highly-charged heavy ions was investigated systematically in a projectile energy (Ep) regime between 1.4 and 420 MeV/u. The absolute cross sections σ(q) for the production of Ar recoil-ions with charge state q decrease smoothly with (Ep) for q ≤ 8, whereas a distinct maximum in the Ep-dependence can be observed for higher q. Furthermore, for 1.4 MeV/u U32+ and 5.9 MeV/u U65+ impact on Ne, a new experimental technique was applied allowing the simultaneous determination of q and of the transverse (with respect to the beam axis) recoil-ion momentum pR⊥. From the good agreement of these differential absolute cross sections with the results of n-body classical trajectory Monte Carlo (nCTMC) calculations we conclude that the trajectories of the heavy nuclei are influenced considerably by the interaction with the target electrons as has been predicted by theory. © 1989.