Non-Self-Sustained Glow Discharges in Atmospheric-Pressure Inert and Molecular Gases in a Three-Electrode Configuration

Non-self-sustained dc glow discharges in various gases at atmospheric pressure were created in a three-electrode configuration at currents of several hundred milliamperes. A self-sustained dc normal atmospheric-pressure glow discharge in inert (helium and argon) gas served as a “plasma cathode” for the main discharge at a gap of 30 mm in inert or molecular (carbon dioxide, nitrogen, and air) gas. In molecular gases, two forms of the positive column simultaneously exist in one discharge gap: constricted and diffuse.