Field-aligned electron density irregularities near 500 km Equator to polar cap topside sounder observations

Journal Article · Sat Jun 01 04:00:00 EDT 1985 · Radio Sci.; (United States)

DOI:https://doi.org/10.1029/RS020i003p00477· OSTI ID:6162933

Benson, R F

In addition to spread F, evidence for field-aligned electron density irregularities is commonly observed on Alouette 2 topside sounder ionograms recorded near perigee (500 km). This evidence is provided by distinctive signal returns from sounder-generated Z mode waves. At low latitudes these waves become guided in wave ducts caused by field-aligned electron density irregularities and give rise to strong long-duration echoes. At high latitudes, extending well into the polar cap, these Z mode waves (and stimulated electrostatic waves at the plasma frequency) produce a series of vertical bars on the ionogram display as the satellite traverses discrete field-aligned density structures. The radio frequency (RF) noise environment to be expected in the 400 to 500 km altitude region from low to high latitudes was examined by analyzing perigee Alouette 2 topside sounder data. All observed noise bands were scaled on nearly 200 topside sounder ionograms recorded near perigee at low, mid, and high latitude telemetry stations. The minimum and maximum frequencies of each noise band were entered into a data base or computer analysis. The signals of primary interest in the perigee study were found to be sounder-generated. 15 references.

• Research Organization: Goddard Space Flight Center, Greenbelt, MD
• OSTI ID: 6162933
• Journal Information: Radio Sci.; (United States), Journal Name: Radio Sci.; (United States) Vol. 20; ISSN RASCA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
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71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AIRCRAFT
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EARTH ATMOSPHERE
ELECTROMAGNETIC RADIATION
ELECTRON DENSITY
IONOSPHERE
PLANETARY IONOSPHERES
PLASMA
PLASMA WAVES
RADIATIONS
RADIOWAVE RADIATION
SPACE SHUTTLES
SPACE VEHICLES
VEHICLES