Critical Ionization Velocity Effects in the Inner Coma of Comet Halley: Measurements by Vega-2

  1. Thomas J. Birmingham and
  2. Alexander J. Dessler
  1. A.A. Galeev1,
  2. K.I. Gringauz1,
  3. S.I. Klimov1,
  4. A.P. Remizov1,
  5. R.Z. Sagdeev1,
  6. S.P. Savin1,
  7. A.Yu. Sokolov1,
  8. M.I. Verigin1 and
  9. K. Szego2

Published Online: 19 MAR 2013

DOI: 10.1029/SP027p0198

Comet Encounters

Comet Encounters

How to Cite

Galeev, A.A., Gringauz, K.I., Klimov, S.I., Remizov, A.P., Sagdeev, R.Z., Savin, S.P., Sokolov, A.Yu., Verigin, M.I. and Szego, K. (1988) Critical Ionization Velocity Effects in the Inner Coma of Comet Halley: Measurements by Vega-2, in Comet Encounters (eds T. J. Birmingham and A. J. Dessler), American Geophysical Union, Washington, D.C.. doi: 10.1029/SP027p0198

Author Information

  1. 1

    Space Research Institute, Moscow

  2. 2

    Central Research Institute of Physics, Budapest

Publication History

  1. Published Online: 19 MAR 2013
  2. Published Print: 1 JAN 1988

ISBN Information

Print ISBN: 9780875902395

Online ISBN: 9781118668757

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Keywords:

  • Anisotropic distributions;
  • Cometary ram analyser (CRA);
  • Critical ionization velocity (CIV) effects;
  • Electric field spectrum;
  • Plasma velocity;
  • Wave measurements and plasma density

Summary

Plasma density and plasma wave measurements aboard the “Vega-2” spacecraft discovered two plasma density enhancements in the inner coma of comet Halley that are accompanied by bursts of plasma waves in the lower-hybrid frequency rapge. These events are explained by the critical ionization velocity (CIV) effects of Alfvén. The persistent bursty plasma wave activity and the intermittent plasma density growth toward the cometary nucleus indicate that the CIV effect contributes to the ionization of the cometary gas.