Abstract
Finite basis diagonalizations were used to calculate the He and H-ground state energies and the He and H-ground state single and double ionization cross sections were calculated using the first Bom approximation at several different ion-atom collision energies. The ground state energies for each atom converged nicely to the measured values as did the He single ionization cross sections. Because there is no known previous data for H-single ionization cross sections by bare projectiles at energies where the first Bom approximation is valid, no comparison could be made but our cross sections showed very good convergence at high energies with respect to the basis. We hope our results will be a guide to future experimental and theoretical work. The double ionization cross sections showed reasonable convergence for He, but for H-converged double ionization cross sections were not obtained. Possible reasons for this are discussed. The high energy ratio of double to single ionization for H-remains an important quantity that needs to be both theoretically and experimentally investigated.
Saunders, Anna Windsor (1996). First Born calculations of the single and double ionization of H- by bare-ion projectiles. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1996 -THESIS -S28.