Radar interferometer observations and theory of plasma irregularities in the auroral ionosphere
The radar interferometer technique first used at the equator in Peru is also a very powerful means for studying auroral plasma instabilities. It is shown to be a very useful tool for probing the essentially two-dimensional turbulence associated with the auroral plasma instabilities. The horizontal interferometer successfully measured the transverse vector electron drift velocities and the electric fields associated with radio aurora and visual discrete auroral arcs. The technique works well for a variety of radar auroral echoing types including diffuse with structure and discrete. The interferometer observations generally show that separate echoing regions within the scattering volume are responsible for composite spectra (e.g. type I and type II spectral features occurring simultaneously within the same spectrum). Kilometer scale (lambda approx. 50 km +/- 20 km) wave-like structures are often observed along the radar line-of-sight during intense magnetic storms (K/sub p/ > 6). Quasi-periodic temporal variations in the horizontal drift velocity and in the mean Doppler shift of the power spectra were also observed, and these appear to be associated with Pi micropulsations and perhaps kilometer scale gradient drift waves. A new spectral type, referred to here as type IV, was identified and is shown to be probably a type I spectrum.
- Research Organization:
- Cornell Univ., Ithaca, NY (USA)
- OSTI ID:
- 6059253
- Resource Relation:
- Other Information: Thesis (Ph. D.)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GENERAL PHYSICS
AURORAL ZONES
PLASMA INSTABILITY
IONOSPHERE
ELECTRON DRIFT
INTERFEROMETERS
MAGNETIC STORMS
RADAR
EARTH ATMOSPHERE
INSTABILITY
MEASURING INSTRUMENTS
PLANETARY IONOSPHERES
RANGE FINDERS
640201* - Atmospheric Physics- Auroral
Ionospheric
& Magetospheric Phenomena