Simulation studies on argon glow discharges established between flat disc electrodes, at pressure × electrode separation (pd) of 45 Pa cm are reported, with special attention to heavy‐particle processes including excitation‐induced light emission. The discharges are investigated through self‐consistent hybrid modelling, consisting of a fluid description for components near local hydrodynamic equilibrium (slow electrons and ions), and Monte Carlo treatment of energetic electrons and heavy particles (ions and neutral atoms). The light emission profiles are analyzed for a wide range of operating conditions. The numerical results for the relative intensities and the shapes of the negative glow (created by electron impact excitation) and the cathode glow (created by heavy particle impact excitation) are in good agreement with experimental data obtained by Maric´ et al. © 2004 American Institute of Physics