Accession Number : AD0283376

Title :   STUDY OF PLASMA AMPLIFIERS

Descriptive Note : Final rept.

Corporate Author : MICROWAVE ASSOCIATES INC BURLINGTON MA

Personal Author(s) : COCCOLI, J.

Report Date : 20 APR 1962

Pagination or Media Count : 46

Abstract : The theories for several fast wave amplification processes f microwave radiation propagating in a plasma in a magnetic field are indicated. The amplification due to the minute relativistic mass change of the plasma electrons as predicted by Bekefi, Hirshfield, and Brown (Ph s of Flui s, 2:173, 1961) is compared with the process predicted by Chow and Pantell (MLR Stanford U., Oct 61) which depends on the Doppler shift phenomenon. The two theories predict different behavior for the gain near waveguide cutoff. A third mechanism is also considered in which electrons in an emitting phase remain in the waveguide interaction region for a longer tim than t ose in an absorbing phase, due to forces arising from the transverse r.f. magnetic field. The results of some preliminary experiments are also discussed. Measurements were taken of the absorption coefficient of the plasma column as a function of the microwave frequency. T e electrons in the column pass through an r.f. heating cavity before entering the interaction waveguide. Irregularities in the narrow absorption curves may indicate the onset of gain as predicted by theory. (Author)

Descriptors :   *EXTREMELY HIGH FREQUENCY, *MICROWAVE AMPLIFIERS, *MICROWAVES, *PLASMAS(PHYSICS), DIFFERENCE EQUATIONS, MATHEMATICAL ANALYSIS.

Distribution Statement : APPROVED FOR PUBLIC RELEASE