Stability of a magnetized Hall plasma discharge

Using recent experimental data on the time-averaged, spatially varying plas ma properties within a Hall discharge plasma, we present in this article, a theoretical study of the response of this plasma to small (linear) perturb ations in its properties. As a starting point for this analysis, we assume a two-dimensional fluid description that includes a simplified equation for the electron energy, and constrain the azimuthal wave vector such that we excite only the dominant (m=1) azimuthal modes. The growth rate and frequen cies of predominantly axial and azimuthally propagating plasma disturbances are obtained by numerical solution of the resulting eigenvalue problem und er a quasiuniform plasma condition, along the entire discharge channel. The results identify the persistence of a low frequency instability that is as sociated with the ionization process, concentrated largely in the vicinity of the exit plane, where the magnetic field is at its maximum value, consis tent with experimental observations for the relatively low operating voltag es (similar to 100 V) considered in this study. (C) 2001 American Institute of Physics.