IONIZATION OF NEUTRAL ATOMS WITH OUTER 2P AND 3P ELECTRONS BY ELECTRON AND PROTON IMPACT

The Born approximation is used to calculate cross sections for the ionization by electron and proton impact of all neutral atomic systems in the sequences boron to neon and aluminium to argon. Possible exchange between the incident and atomic electrons is approximately taken into account using the Ochkur approximation to the exchange amplitude. In the cases where experimental data exist for comparison there is agreement at high energies to within about a factor of 2, a discrepancy which may be partly explained by the simple approximation made to the true wave function of the ejected electron.