2-DIMENSIONAL MODEL OF A DIRECT-CURRENT GLOW-DISCHARGE - DESCRIPTION OF THE ELECTRONS, ARGON IONS, AND FAST ARGON ATOMS

To improve the analytical results of techniques that use the glow disc harge as spectroscopic source, a good insight into the glow discharge is desirable, This can be obtained by mathematical modeling. In this w ork, a two-dimensional model is developed to describe the electrons, a rgon ions, and fast argon atoms in a direct current glow discharge in argon, The model consists of a Monte Carlo model for the fast electron s, a Monte Carlo model for the argon ions and fast argon atoms in the cathode dark space, and a fluid model for the argon ions and slow elec trons. Results in two dimensions are presented for a standard flat cel l of the VG 9000 glow discharge mass spectrometer (VG Elemental, Fison s); they include the densities, mean energies, and collision rates of the plasma species, the potential distribution, and the axial and radi al electric fields.