Single and double ionization inC6++Hecollisions

Abstract

Single- and double-ionization processes in ${\mathrm{C}}^{6+}$ collisions with the He atom at an incident energy of $100$ MeV/amu are studied by direct solution of the time-dependent Schr\"odinger equation. A time-dependent close-coupling method based on an expansion of a one-electron three-dimensional wave function in the field of He${}^{+}$ is used to calculate single-ionization cross sections. A time-dependent close-coupling method based on an expansion of a two-electron six-dimensional wave function in the field of He${}^{2+}$ is used to calculate single- and double-ionization cross sections. Electron energy and angle differential cross sections for single ionization are presented for various projectile impact parameters. For relatively large impact parameters, the differential cross sections are in qualitative agreement with ion-atom experiments. Electron energy and angle differential cross sections for double ionization are also presented for a relatively large projectile impact parameter.