A Caltech Library Service

Interaction of a Modulated Electron Beam with a Plasma

Boyd, G. D. and Gould, R. W. and Field, L. M. (1961) Interaction of a Modulated Electron Beam with a Plasma. Proceedings of the IRE, 49 (12). pp. 1906-1916. ISSN 0096-8390. doi:10.1109/JRPROC.1961.287719.

PDF - Published Version
See Usage Policy.

[img] PDF - Accepted Version
See Usage Policy.


Use this Persistent URL to link to this item:


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 was experimentally observed for the first time at a microwave frequency equal to the plasma frequency. Approximate theories of the effects of 1) plasma-electron collision frequencies, 2) plasma-electron thermal velocities and 3) finite beam diameter, are given. In a second experiment the interaction between a modulated electron beam and a slow electrostatic wave on a plasma column has been 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 here the plasma colum replaces the usual helical slow-wave circuit. The theory predicting rates of growth is presented and compared with the experimental results.

Item Type:Article
Related URLs:
URLURL TypeDescription ItemThesis
Additional Information:© 1961 IEEE. Reprinted with permission. Received by the IRE, August 7, 1961. This work was supported by the Office of Naval Research, Contract NONR 220(13). A great deal of credit for the success of these experiments is attributable to A.F. Carpenter, whose skill and patience in the fabrication of the glass tubes is gratefully acknowledged. Fruitful discussions were enjoyed with Dr. A.W. Trivelpiece. The continuing support of the Office of Naval Research is very gratefully acknowledged.
Group:Electron Tube and Microwave Laboratory
Funding AgencyGrant Number
Office of Naval Research (ONR)220(13)
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Electron Tube and Microwave Laboratory Technical Report18
Issue or Number:12
Record Number:CaltechAUTHORS:BOYprocire61
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:9815
Deposited By: Archive Administrator
Deposited On:19 Mar 2008
Last Modified:19 May 2023 17:45

Repository Staff Only: item control page