Electron collisions with positive ions. Final report, June 15, 1990--June 14, 1992

This report concerns a program of computation of cross sections for electron impact excitation and ionization of ions. A review of progress made in the 1980s for calculations on electron impact excitation of atoms and ions for low and intermediate energy ranges concludes that the effect of continuum channels is very important to include in close coupling calculations. This may be achieved by use of pseudostates or the coupled-channels optical-potential method or the intermediate energy R-matrix method. Those methods have been applied mainly to electron atom scattering to date and much remains to be accomplished in electron-ion scattering. Further, for multicharged ions, contributions of excitation-autoionization and resonant-excitation-double-autoionization to total ionization cross sections are important and underscore the role of two-electron correlation effects