Accession Number : AD0697363

Title :   UHF-PLASMA INTERACTION--THE TWO-STREAM INSTABILITY OF A current-CARRYING PLASMA,

Corporate Author : STANFORD UNIV CALIF INST FOR PLASMA RESEARCH

Personal Author(s) : Hosea,J.

Report Date : AUG 1966

Pagination or Media Count : 152

Abstract : The 'collective' space charge interaction between the electron and ion streams of a current-carrying plasma results in the enhancement of electrostatic oscillations carried by the two streams. When the relative drift velocity between the electrons and ions exceeds a critical value of the order of the electron thermal velocity, some oscillations begin to grow exponentially in amplitude and the 'to-stream instability of a current-carrying plasma' ensues. This study comprises a thorough experimental investigation of the onset properties of this instability and an examination of its nonlinear properties. The experimental apparatus consists of a UHF TM010 cavity loaded along its axis with a plasma column produced by a pulsed P.I.G. reflex discharge. The electric field of the cavity serves to excite a UHF current along the plasma column which in turn can produce the two-stream instability during every half-cycle. The time scale for electrostatic interaction is much shorter than the UHF half-period. Considerable attention was given to the design of this appratus so that it would be amenable to the Stringer formulation of the linearized two-stream theory and thus would permit a meaningful comparison between the experimental and theoretical instability onset conditions. (Author)

Descriptors :   (*PLASMA MEDIUM, ELECTRIC CURRENTS), STABILITY, PLASMA OSCILLATION, SPACE CHARGE, ULTRAHIGH FREQUENCY, CAVITY RESONATORS

Subject Categories : Plasma Physics and Magnetohydrodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE