Generation of ELF and VLF waves by a thermal instability excited in the HF heater-modulated polar electrojet

Research output: Contribution to journalArticle

Abstract

A thermal instability responding to the modulation of polar electrojet by HF heater as a potential efficient mechanism for the generation of ELF and VLF waves has been investigated. It is shown that a positive feedback through the electron-neutral collisional heating process can cause the transient response of the plasma to the modulated HF heater to grow exponentially. Considering a sinusoidally modulated HF heater wave having its field amplitude proportional to |cosω-1$/t/2|, the threshold fields of the thermal instability under normal electrojet conditions are found to be about 1.6 V m-1 for the o mode and x mode operation respectively. For a heater wave field of 2 V m-1, the instability can be excited by the x mode heater within a few milliseconds and also by the o mode heater but taking about 9 times as long.

Original languageEnglish (US)
Pages (from-to)1019-1027
Number of pages9
JournalRadio Science
Volume28
Issue number6 pt 2
StatePublished - Nov 1993

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electrojets
thermal instability
electrojet
heaters
Industrial heating
Transient analysis
Modulation
Feedback
Plasmas
positive feedback
Electrons
transient response
wave field
heater
Hot Temperature
heating
modulation
plasma
electron
thresholds

ASJC Scopus subject areas

  • Computer Networks and Communications
  • Atmospheric Science
  • Computers in Earth Sciences
  • Geochemistry and Petrology
  • Geophysics
  • Instrumentation

Cite this

Generation of ELF and VLF waves by a thermal instability excited in the HF heater-modulated polar electrojet. / Kuo, Spencer.

In: Radio Science, Vol. 28, No. 6 pt 2, 11.1993, p. 1019-1027.

Research output: Contribution to journalArticle

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