Correlation between reversion of signs of the electric field in the near-cathode plasma and anode fall potential in a short DC glow discharge

Relatively simple probe and optical experiments were performed, confirming the presence of two main scenarios for the formation of the longitudinal characteristics of a short (without positive column) glow discharge. 1. At low pressures, when there is a single point of sign reverse of the electric field at the maximum of the plasma density, the anode fall is negative and the magnitude of the anode fall is small, there is no ionization and the anode area is dark. 2. Upon an increase in pressure, two points of field reversal are to be expected, the sign of the anode fall is positive and the anode fall of potential is comparable to the gas ionization potential; therefore, the intensive ionization directly at the anode, which glows brightly, takes place.