Accession Number:

AD0643532

Title:

TEMPERATURE MEASUREMENTS ON ELECTRON AND ION BEAMS,

Descriptive Note:

Corporate Author:

HUGHES RESEARCH LABS MALIBU CALIF

Personal Author(s):

Report Date:

1966-08-01

Pagination or Media Count:

41.0

Abstract:

The retarding potential method produced temperature measurement accuracies which are comparable to or better than those possible with the best pyrometers or thermocouples. The method is limited to a close-spaced planar diode, with a collimating magnetic field to avoid nonaxial forces. In addition, the complete hemisphere of angles in the distribution must contribute in order to yield the simple current-voltage relation i v e to the v power v 0. In contrast, the total energy distribution function for a Maxwellian reads i v 1-v e to the v power. It may be measured with an energy spectrometer which is sensitive to the total energy only. Such an instrument is described. In this case the source and spectrometer may be far apart. On its way to the spectrometer the beam may be accelerated, focused, or generally subjected to nonaxial forces. Furthermore, completeness of the angular distribution is not required. A graphical method for accurate temperature determination from a recorded energy spectrum is described. As examples, the electron spectrum from a vidicon gun with oxide coated cathode and the ion spectrum from the plasma of a plane parallel cesium diode are shown. Author

Subject Categories:

  • Atomic and Molecular Physics and Spectroscopy
  • Thermodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE