The plasma wave environment of an auroral arc. 3. VLF hiss

Journal Article · Wed Jul 01 04:00:00 EDT 1987 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA092iA07p07581· OSTI ID:5595638

Bering, E A ^[1]; Maggs, J E ^[2]; Anderson, H R ^[3]

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1. Univ. of Houston, TX (United States)
2. Univ. of California, Los Angeles (United States)
3. Science Applications International Corp., Bellevue, WA (United States)

Intense auroral hiss was observed by a sounding rocket payload under circumstances that have allowed detailed comparison of the hiss spectrum with the predictions of a convective beam amplification hiss production model. Auroral hiss was first encountered at the poleward edge of the diffuse aurora, and was observed for the rest of the flight. A maximum intensity of 10{sup {minus}8}(V/m){sup 2}/Hz at 30 kHz was seen in the dark region. Electron distribution functions were seen with {delta}f/{delta}v{sub {parallel}} > 0 and a large enough slope to have produced appreciable VLF amplification. These distributions were found in a region a few kilometers wide on the equatorward boundary of the arc. A model distribution function has been fitted to one of the observed distributions and used as input into an auroral beam noise generation model. Reasonable assumptions about the distribution of cold plasma and width of the unstable region yields a predicted VLF spectrum in good agreement with observation. Several secondary results were also obtained. The observed VLF hiss does not appear to have been produced by a payload-plasma interaction. The intensity of the hiss measured in situ, above the ionosphere, was greater equatorward of the arc than within the arc, thus ruling out the ionospheric transmission model as an explanation for this intensity pattern. Quasi-linear back reaction on the electron distribution was not found to be significant in this case. The correlation between 0.1-0.7 keV electron flux and hiss intensity was not better than the correlation with the flux of 5-keV electrons.

• OSTI ID: 5595638
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 92:A7; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

661320* -- Auroral
Ionospheric
& Magnetospheric Phenomena-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AMPLIFICATION
AURORAE
AURORAL HISS
COLD PLASMA
COMPARATIVE EVALUATIONS
CORRELATIONS
DECAY INSTABILITY
DISTRIBUTION FUNCTIONS
EARTH ATMOSPHERE
ELECTROMAGNETIC RADIATION
ELECTRONS
ELEMENTARY PARTICLES
EVALUATION
FERMIONS
FUNCTIONS
INSTABILITY
IONOSPHERE
LEPTONS
MATHEMATICAL MODELS
MONITORING
PLANETARY IONOSPHERES
PLASMA
PLASMA INSTABILITY
PLASMA WAVES
RADIATIONS
ROCKETS
WAVE PROPAGATION