Abstract
The target continuum has a large effect on electron and positron scattering to low-lying states of atoms. In addition to ionization the continuum of positron scattering includes positronium-formation channels. The equivalent-local coupled-channel-optical method is a numerically simple way of including the continuum in a coupled-channel calculation. Here it is tested by its prediction of total cross sections for continuum and discrete excitations on inert-gas targets.