Elf Waves and Ion Resonances Produced by an Electron Beam Emitting Rocket in the Ionosphere

  1. Tom Chang,
  2. M. K. Hudson,
  3. J. R. Jasperse,
  4. R. G. Johnson,
  5. P. M. Kintner and
  6. M. Schulz
  1. J. R. Winckler,
  2. Y. Abe and
  3. K. N. Erickson

Published Online: 21 MAR 2013

DOI: 10.1029/GM038p0191

Ion Acceleration in the Magnetosphere and Ionosphere

Ion Acceleration in the Magnetosphere and Ionosphere

How to Cite

Winckler, J. R., Abe, Y. and Erickson, K. N. (1986) Elf Waves and Ion Resonances Produced by an Electron Beam Emitting Rocket in the Ionosphere, in Ion Acceleration in the Magnetosphere and Ionosphere (eds T. Chang, M. K. Hudson, J. R. Jasperse, R. G. Johnson, P. M. Kintner and M. Schulz), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM038p0191

Author Information

  1. School of Physics and Astronomy, University of Minnesota Minneapolis, Minnesota 55455

Publication History

  1. Published Online: 21 MAR 2013
  2. Published Print: 1 JAN 1986

ISBN Information

Print ISBN: 9780875900636

Online ISBN: 9781118664216

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Keywords:

  • Magnetosphere—Congresses;
  • Ionosphere—Congresses;
  • Ion flow dynamics—Congresses;
  • Space plasmas—Congresses

Summary

The injection of a powerful electron beam into the auroral ionosphere produces a myriad of large electric signals which have been studied on a free flying plasma diagnostics payload during the ECHO 6 experiment. The primary interaction of the electron beam was to produce a hot plasma region with characteristic electron energies of 100 ev. When the beam was injected in a nearly transverse spiral the most intense region extended to 60 m perpendicular to the beam but was still detectable at 110 m. Strong electric fields were observed in the hot plasma region consisting of a quasi-dc component directed towards the beam sector with large superposed low-frequency wave variations. Harmonics were seen spaced about 40 Hz near the O+ gyro frequency with the fundamental at 75 Hz or 3/2 the 50 Hz fundamental. When the beam was injected upward parallel to B the hot plasma region and quasi-dc fields were not observed and were probably within the 40 m radius where measurements began. In this case the proton gyro wave consistently appeared with the electric vector linearly polarized in a direction transverse to the radial direction from the beam. In addition a continuous wave spectrum extended from about 200 Hz to above the system Nyquist frequency at 1250 Hz. These natural ion resonances appear to be in the electrostatic mode and may be produced by a current-driven instability as described by Kindel and Kennel. The 1 kHz accelerator pulsing frequency was also consistently observed to the largest distance surveyed of 110 m. The wave activity across the entire ELF spectrum was strongly suppressed when the system passed through field lines containing auroral activity, which together with other evidence indicates that the basic wave production mechanism was the negative potentials of the beam combined with urrents flowing in the hot plasma region as well as return currents necessary for neutralizing the positive potential of the accelerator payload. Vigorous wave production in the lower hybrid and whistler mode frequency regions was observed but will not be discussed in detail.