The effect of a radial electric field on the potential relaxation instability (PRI), excited by a positively biased electrode in a single-ended Q-machine, is investigated experimentally. When the radial electric field Er in the boundary region between the bulk of the plasma and the thin plasma outside is directed inward, the PRI is suppressed, and a maximum stable axial current flows. However, an outward pointing Er leads to an amplification of the PRI due to the enhancement of the radial ion loss, giving rise to a strong current chopping.
ASJC Scopus subject areas
- Physics and Astronomy(all)