VACUUM TUBE RESEARCH PROJECT.
Abstract
The first plasma amplifier was successfully operated and interaction between the plasma electrons and the electron beam was detected. A 5 db variation in gain with arc current results and the arc current required for maximum gain varies approximately as the square of the operating frequency. Reflection of electromagnetic waves from a cylindrical column of plasma placed in a rectangular waveguide indicates two maxima in the reflection coefficient instead of a single maxima as predicted by the elementary theory. This effect has sometimes been noticed by other workers but it has no accepted explanation. The change in the resonant frequency of the plasma column due to a radial variation in electron density has been computed and it is found that if the density varies by less than a factor of 2 the resonant frequency is determined by the average electron density. The normalized surface admittance just above a thin strip beam in Brillouin flow was found for two cases. Several of the design relations for thin beam M-type backward-wave oscillators were obtained. Propagation of space charge waves in an accelerated electron beam of finite diameter is being investigated. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 31, 1957
- Accession Number
- AD0693024
Entities
People
- Lester M. Field
- Roy W. Gould
Organizations
- California Institute of Technology