IONIZATION-INSTABILITY OF MAGNETIZED DUSTY GASES

The ionization instability of a magnetized dusty plasma in which the n eutral gas is ionized by a constant influx of energetic electrons is i nvestigated. We have employed a multi-fluid dusty plasma model to deri ve dispersion relations for electrostatic dusty plasma waves in the pr esence of various drags (viz. frictional drag on the dust grains exert ed by the neutral atoms, ion losses, ion viscosity, collisions of the ions with the neutrals, and ion losses to the walls or to the dust gra ins) as well as a source term which accounts for the creation of new i ons through ionization of the neutral gas. The dispersion relations ar e analysed to demonstrate the ionization instability of long wavelengt h (with respect to the ion and dust gyroradii) and intermediate wavele ngth [shorter (longer) than the dust (ion) gyroradius] electrostatic f luctuations. The relevance of our investigation to low-temperature ast rophysical and laboratory plasmas is pointed out.