Electrostatic Sound Wave Modes in a Plasma

Abstract

To test the hypothesis that ion waves are a source of lowfrequency fluctaations occuring in the parameters of d-c discharges, d-c mercury-vapor discharges of approximately 1 mu pressure were studied in tubes containing an oxide-coated spiral cathode, mounted transversely in a Mo cup. Results suggest that an electrostatic sound wave mechanism may be operating, and that it is enhanced by the presence of a constriction. (P.C.H.)