Accession Number : ADP006516

Title :   Vehicle Charging in Low Density Plasmas,

Corporate Author : NORWEGIAN DEFENCE RESEARCH ESTABLISHMENT KJELLER

Personal Author(s) : Maehlum, B. N. ; Troim, J.

Report Date : OCT 1990

Pagination or Media Count : 11

Abstract : Studies of electrical charging of space vehicles have been reported in a number of papers in the last ten years. These studies are based on charging due to onboard electron and ion accelerators as well as charging due to thermal and energetic electrically charged particles impinging on the surface of the vehicle. In spite of this significant effort made in the field both theoretically and experimentally, the vehicle charging problem is far from being completely understood. Part of the problem relates to the effects of the plasma disturbances created by the beam. Several attempts have been made with a varying degree of success to simulate space plasma processes in large plasma chambers. The celebrated studies in the large chamber at Johnson Space Center in Houston by Bernstein and collaborators (1) show that the plasma may be very disturbed in the presence of a beam of fast electrons by a BPD process ( Beam Plasma Discharge ). This process was expected also to explain phenomena observed in the upper atmosphere and possibly various aspects of the vehicle charging. However, there are still some doubts as to whether the BPD really occurs in space, and the significance of the laboratory simulation experiments conducted in the past remains obscure. In this paper we present a number of high vehicle charging generated by electron beams and discuss how this charging depends on the characteristics of the plasma environment Also, some results from a simulation study of these problems conducted in the NDRE plasma chamber are reviewed.

Descriptors :   *SPACECRAFT CHARGING, ATMOSPHERES, CHAMBERS, CHARGED PARTICLES, ELECTRON BEAMS, ELECTRONS, ION ACCELERATORS, ONBOARD, PARTICLES, SIMULATION, SPACECRAFT, SURFACES, UPPER ATMOSPHERE, SPACE ENVIRONMENTS, ELECTROMAGNETIC ENVIRONMENTS, NORWAY, ION BEAMS, PLASMAS(PHYSICS).

Subject Categories : Astronautics
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE