Longitudinal variations of plasmapause radius and the propagation of VLF noise within small (. delta. Lapprox. 0. 5) extensions of the plasmasphere

Journal Article · Tue Sep 01 00:00:00 EDT 1981 · Geophys. Res. Lett.; (United States)

DOI:https://doi.org/10.1029/GL008i009p00980· OSTI ID:5936529

Smith, A J; Carpenter, D L; Lester, M

Simultaneous broadband whistler recordings made during the International Magnetospheric Study (IMS) at the two Antarctic stations Halley and Siple have been used to study longitudinal variations in the radius of the plasma-pause observed during local afternoon. In both of the two periods studied thus far, whistler-derived equatorial electron density profiles imply an increase in plasmapause radius between the longitudes of Siple and Halley (..delta..phiapprox.30/sup 0/) of ..delta..Lapprox.0.5. Intense VLF noise (..cap alpha..2.5 kHz) was observed at Halley but not at Siple, and by echo analysis its propagation path was identified with that of a whistler component travelling close to the plasmapause within the region of larger radius. This leads to the conclusion that the noise was generated by a gyroresonance instability when energetic electrons (typically 10 keV), drifting eastwards in the plasmatrough, encountered enhanced plasma density in the small extension of the plasmaphere.

• Research Organization: British Antarctic Survey, Cambridge, England
• OSTI ID: 5936529
• Journal Information: Geophys. Res. Lett.; (United States), Journal Name: Geophys. Res. Lett.; (United States) Vol. 8:9; ISSN GPRLA
• Country of Publication: United States
• Language: English

Related Subjects

640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
EARTH ATMOSPHERE
ELECTROMAGNETIC RADIATION
ELECTRON DENSITY
GEOGRAPHICAL VARIATIONS
MAGNETOSPHERE
NOISE
PLASMAPAUSE
PLASMASPHERE
RADIATIONS
RADIO NOISE
RADIOWAVE RADIATION
VARIATIONS
WAVE PROPAGATION
WHISTLERS