Velocity selection for ionization fronts in planar dc gas-discharge system with high-ohmic electrode
We deal with the theoretical investigation of pattern formation in a planar dc gas-discharge system with a high-ohmic electrode. In particular, we are interested in a description of electric breakdown in
the low-current Townsend mode of discharge operation. Using the
adiabatic description of electrons and two-scale expansion one can
show that the discharge in this mode is governed by a two-component
reaction-diffusion system, which provides a quantitative system
description on the macroscopic time scale. On this base ionization
fronts being nontrivial solutions of this reaction-diffusion system
are discussed in details. In particular, velocity and initial
condition selection are investigated in one- and two spatial
dimensions.