Born cross sections for fast, low-charge-state uranium ions colliding with lithium atoms and ions

Abstract

Born-approximation calculations of various inelastic-scattering cross sections for collisions between U'+ (q = 1, 2, and 4) ions and Li atoms and ions are presented. The energies considered are in the 10-100-MeV/amu regime, with an emphasis on providing results useful in assessing the importance of various phenomena in heavy-ion, inertialconfinement-fusion reactor concepts for the case of U'+ beams of 10 -20 GeV. Estimates of the U'+ electron-loss cross sections are given for collisions with lithium in all charge states; order-of-magnitude differences between Li atoms and ions are predicted. Calculations of the cross sections for the ionization of Li atoms and ions due to the impact of fast U'+ ions are also given. The lithium discrete-state and ionization contributions to the sum-rule asymptotic cross sections are computed for the cases of Li' and Li'+. Ionization is the dominate contributor ( & 50%) for these collisions, in contrast to the case of proton impact at similar speeds ( 10% for Li ). %e also estimate the mean energies of the electrons produced in these ionizing collisions and. obtain results more than an order of magnitude larger than in the case of proton impact.