Accession Number:

ADA275570

Title:

Active Electron and Ion Beam Experiments in Space

Descriptive Note:

Final rept. 18 Feb 1988-31 Dec 1992

Corporate Author:

CALIFORNIA UNIV LOS ANGELES INST OF GEOPHYSICS AND PLANETARY PHYSICS

Report Date:

1993-02-01

Pagination or Media Count:

52.0

Abstract:

The basic physical processes that occur during the active electron beam experiments in the ionosphere are examined using multi-dimensional particle simulations. A three-dimensional isolated-system, electrostatic model is used to establish the characteristic time scales associated with injection and to investigate the processes of spacecraft charging and the loss of coherence during beam propagation. Two-dimensional electromagnetic simulations indicate that the beam-plasma interaction leads to the formation of a current structure which acts like an antenna and emits whistler waves in a coherent manner. An ion emitter instrument which injects indium ions will be used during the Geotail and Cluster satellite missions to control the spacecraft potential to be near that of the ambient plasma. To understand the beam-plasma interaction that can occur due to the ejection of the ion beam into various regions of the Earths magnetosphere, a linear theory study is presented to see whether particular combinations of ambient plasma parameters and ion beam emission modes exist, such that plasma instabilities may be excited.

Subject Categories:

  • Atmospheric Physics
  • Particle Accelerators
  • Plasma Physics and Magnetohydrodynamics
  • Unmanned Spacecraft

Distribution Statement:

APPROVED FOR PUBLIC RELEASE