Electron Beam Experiments at High Altitudes,

Abstract

Experiments with the electron gun on the SCATHA satellite produced evidence of beam-plasma interactions, and heating of the low energy electrons around the satellite. These experiments were conducted near geosynchronous orbit, in the dusk, bulge, and plasma sheet, with one short operation in the lobe regions, providing a range of ambient plasma densities. The electron gun was operated at 50 eV, with beam currents of 1, 10 and 100 microAmps. Data from electrostatic analyzers and the DC electric field experiment show that the satellite charged to near the beam energy in sunlight, if the beam current was distribution functions which had peaks, or plateaus at energies greater than the satellite potential. These measurements indicate heating of the ambient plasma, at several Debye lengths from the satellite (several 10's of meters), with the heated plasma then accelerated into the satellite. It is likely that the 'ambient' plasma is in fact the photoelectron sheath generated by the satellite.

Document Details

Document Type
Technical Report
Publication Date
May 01, 1987
Accession Number
ADP005700

Entities

People

  • R. C. Olsen

Organizations

  • University of Alabama in Huntsville

Tags

DTIC Thesaurus Topics

  • Aerospace Environments
  • Altitude
  • Artificial Satellites
  • Distribution Functions
  • Electric Fields
  • Electromagnetic Wave Propagation
  • Electron Beams
  • Electron Guns
  • Electrons
  • Electrostatic Analyzers
  • Geosynchronous Orbits
  • High Altitude
  • Spacecraft
  • Spacecraft Charging
  • Wave Propagation

Fields of Study

  • Physics

Readers

  • Pulsed Power and Plasma Physics.
  • Space/Atmospheric Physics.

Technology Areas

  • Directed Energy
  • Microelectronics
  • Space
  • Space - Hall-Effect Thruster
  • Space - Satellites