Influence of the state of the electron gas on dispersion curves of ionization waves in neon

On the example of neon the onset of a transition is described from a non-hydrodynamic state of the electron gas, which exists at low pressures and currents, to a state where a local hydrodynamics is applicable. In the non-hydrodynamic state the ionization waves are influenced by resonant properties of the electron gas which means that several varieties can be selected on each of the two dispersion curves. With growing current the two parts of dispersion curve of the fast varieties (r and s) merge and this is interpreted as disappearance of the spatial resonance of the electron gas due to an enhancement of the electron Coulomb collisions.The author expresses his gratitude to K.Rohlena and L.Pekárek for helpful discussions.