Coupled-channel calculations of ionization and excitation cross sections for ion-helium collisions

Abstract

Using the semiclassical approximation we calculate cross sections for excitation, single and double ionization of helium in collisions with , and in the energy range between and . The method is the solution of time-dependent coupled-channel equations for the amplitudes of two-electron basis states. The basis states are obtained by diagonalizing the Hamiltonian of the helium atom in a finite basis of antisymmetrized products of hydrogen-like Slater functions. The projectile-electron interaction takes the retardation effects into account. The results are compared with experimental data and other theoretical approaches.