Generation of ELF and VLF waves by HF heater-modulated polar electrojet via a thermal instability process

Spencer Kuo, M. C. Lee

Research output: Contribution to journalArticle

Abstract

It is shown that a positive feed-back through the electron-neutral collisional heating process can cause the transient response of the plasma to the modulated HG heater to grow exponentially. The threshold fields of the instability under normal electrojet conditions are found to be about 2.25 V/m and 1.13 V/m for the operation of the o-mode and x-mode heaters with a 50% duty cycle, respectively. For a heater wave field of eg 1.5 V/m, the instability can be excited by the x-mode heater within a few tens of millisecond. The predicted dependence of the ELF/VLF radiation amplitude on the percentage of the duty cycle of the HG modulation is identical to that of the recent observational results of Barr and Stubbe (1991). -from Authors

Original languageEnglish (US)
Pages (from-to)189-192
Number of pages4
JournalGeophysical Research Letters
Volume20
Issue number3
StatePublished - 1993

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electrojets
thermal instability
electrojet
heaters
cycles
positive feedback
transient response
wave field
heating
modulation
plasma
electron
thresholds
heater
causes
radiation
electrons

ASJC Scopus subject areas

  • Earth and Planetary Sciences (miscellaneous)

Cite this

Generation of ELF and VLF waves by HF heater-modulated polar electrojet via a thermal instability process. / Kuo, Spencer; Lee, M. C.

In: Geophysical Research Letters, Vol. 20, No. 3, 1993, p. 189-192.

Research output: Contribution to journalArticle

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