Independent electron approximation in collisions of nuclei with atoms

The process of a multielectron transition in an atom taking place during scattering, from an atom, of a structureless charged particle moving at a velocity v is treated in the model of independent particles taking into account antisymmetrisation. In the impact parameter representation, expressions for the probabilities W( rho ) of multielectron transitions between various electronic subshells, multiple ionisation processes and also ionisation transitions leading to excitation of the atomic residual have been obtained. On the basis of the probability formulae, the cross sections for the ionisation of helium atoms resulting in the excitation of the atomic residual to the 2s, 2p, 3s, 3p and 3d states have been calculated. The cross sections obtained are compared with similar cross sections taken from the work of Dalgarno and McDonald and Mapleton.