Interaction of a Modulated Electron Beam with a Plasma

Journal Article · Fri Dec 01 04:00:00 EST 1961 · Proceedings of the IRE

DOI:https://doi.org/10.1109/JRPROC.1961.287719· OSTI ID:4798565

Boyd, G.; Gould, R.; Field, L.

The results of a theoretical and experimental investigation of the high- frequency interaction of an electron beam with a plasma are reported. An electron beam, modulated at a microwave frequency, passes through a uniform region of a mercury arc discharge after which it is demodulated. Exponentially growing wave amplification along the electron beam is experimentally observed for the first time at a microwave frequency equal to the plasma frequency. Approximate theories of the effects of plasmaelectron collision frequencies; plasma-electron thermal velocities; and finite beam diameter are given. The interaction between a modulated electron beam and a slow electrostatic wave on a plasma column is also studied. A strong interaction occurs when the velocity of the electron beam is approximately equal to the velocity of the wave, and the interaction is essentially the same as that which occurs in traveling-wave amplifiers, except that the plasma column replaces the helical slow-wave circuit. The theory predicting rates of growth is presented and compared with the experimental results.

• Research Organization: California Inst. of Technology, Pasadena
• Sponsoring Organization: USDOE
• NSA Number: NSA-16-028295
• OSTI ID: 4798565
• Journal Information: Proceedings of the IRE, Journal Name: Proceedings of the IRE Journal Issue: 12 Vol. 49; ISSN 0096-8390
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

AMPLIFIERS
CIRCUITS
CYLINDERS
ELECTRIC ARCS
ELECTRIC DISCHARGES
ELECTRON BEAMS
ELECTROSTATICS
FREQUENCY
INTERACTIONS
MEASURED VALUES
MERCURY
MICROWAVES
MODULATION
OSCILLATIONS
PHYSICS
PLASMA
PLASMA WAVES
VARIATIONS
VELOCITY