Currents in the Earth's Magnetotail

  1. Thomas A. Potemra
  1. L. A. Frank,
  2. C. Y. Huang and
  3. T. E. Eastman

Published Online: 21 MAR 2013

DOI: 10.1029/GM028p0147

Magnetospheric Currents

Magnetospheric Currents

How to Cite

Frank, L. A., Huang, C. Y. and Eastman, T. E. (1984) Currents in the Earth's Magnetotail, in Magnetospheric Currents (ed T. A. Potemra), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM028p0147

Author Information

  1. Department of Physics and Astronomy, The University of Iowa, Iowa City, Iowa 52242

Publication History

  1. Published Online: 21 MAR 2013
  2. Published Print: 1 JAN 1984

ISBN Information

Print ISBN: 9780875900551

Online ISBN: 9781118664131

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Keywords:

  • Magnetospheric currents—Congresses;
  • Plasma instabilities—Congresses

Summary

Currents in the earth's magnetotail are detected with the plasma instrumentation on board the ISEE-1 spacecraft. Field-aligned currents directed into and out of the ionosphere are found in the boundary layer of the plasma sheet. Typical current densities are in the range of 5×10−9 to 5×10−8 A/m2. These currents are associated with the Region 1 current system that is observed previously at low altitudes. An intense current sheet is shown to exist at a discontinuity in convection electric fields $$(\Delta \bullet {\rm \vec E}\,{\rm < }\,{\rm 0})$$ during a period of great magnetic activity. Electron acceleration, similar to that for electron inverted-V precipitation regions at low altitudes, occurs in this current sheet. Examination of the plasma velocity distributions at a neutral sheet crossing reveals that the neutral sheet current is carried by electrons and protons. The relative directions for the bulk flows of the proton and electron plasmas indicate that the first adiabatic invariant is not conserved for the protons, and quite possibly for the electrons also. These latter findings are in substantial agreement with a neutral sheet model for acceleration of charged particles in the presence of a weak electric field.