Computer simulation of a nitrogen discharge at high overvoltages

A computer simulation was performed for comparison with the experiments by Koppitz (1973) of a transient discharge with a large cross section between parallel plates in nitrogen. The simulation model was based on the continuity equations for electrons, positive ions and excited molecules and on Poisson's equation. Gas photoionization and cathode photoelectron emission are considered as the secondary processes. The streak diagrams of the light output obtained by the simulation agreed well with the experimental ones, particularly for 20-100% overvoltages. The variation of the electron and positive ion densities and the electric field intensity between the electrodes are also given in streak diagrams. These results support the qualitative explanation by Koppitz concerning the role of each of the secondary processes.