Low-frequency drift-wave instability in dc discharges

Abstract

The result for the permittivity of weakly ionized, weakly magnetized plasmas obtained by Kiss'ovski and Shivarova (1995) is analysed aiming at a description of the behaviour of low-frequency instabilities in dc discharges maintained at comparatively high gas pressures. The spectrum and the condition of instability of low-frequency drift waves arising in the discharges under conditions of comparatively high collision frequency ν in ∼ ω ci and finite ion gyroradius ρ i < R are derived. (Here ω ci and ρ i are the ion gyrofrequency and gyroradius, respectively, ν in is the ion-neutral collision frequency and R is the plasma column radius.) Results from numerical analysis are compared with experimental data previously obtained (Kiss'ovski et al 1994).

Low-frequency temperature-dependent plasma discharge instabilities in the presence of external constant electric and magnetic fields

“…In (22), ω pe and ω pi are the electron and ion plasma frequency, respectively. It is easy to solve (22) and obtain the frequency spectra and the imaginary part of ω, i.e. Im(ω) under the conditions ω Ӷ B i ω 2 pi /ν i0 , ω Ӷ |k y u ey | and n e0 n i0 n:…”

“…In addition, we identify a new instability caused by the stimulated scattering of drifting electrons from the relaxation oscillations of the electron temperature. The low-frequency drift-wavetype instability of weakly ionized magnetized plasmas has also been studied [21,22]. In addition, studies on the influence of a magnetic field on the growth of the instabilities in a helium glow discharge and on the existence of the weakly ionized plasma instability caused by the competition between the diffusion and thermodiffusion processes (thermocurrent instability) have also been undertaken [23,24].…”