F region electron temperature signatures of the plasmapause based on Dynamics Explorer 1 and 2 measurements

Journal Article · Tue Mar 01 00:00:00 EST 1988 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA093iA03p01896· OSTI ID:5162072

Brace, L H; Chappell, C R; Chandler, M O; Comfort, R H; Horwitz, J L

Early satellite measurements in the F region found a peak in electron temperature, T/sub e/, at night on L shells that thread the expected location of the equatorial plasmapause. This T/sub e/ enhancement has been attributed to heating by magnetospheric sources. The T/sub e/ peak typically occurs near 60/sup 0/ invariant latitude, moves equatorward during magnetically active periods, and recovers during quieter times in a fashion similar to observed plasmapause behavior. Recent Dynamics Explorer 1 and 2 measurements near 2100 LT have shown that the T/sub e/ peak in that sector occurs on L shells that are either within the gradient of the plasmapause or just equatorward of that location. Dayside T/sub e/ signatures in the F region near 60/sup 0/ invariant latitude also have been reported, but these are observed primarily above 600 km, and their relationship to dayside plasmaspheric features, if any, has been unknown. In this paper we employ a more extensive set of DE-1 and -2 measurements to examine this relationship at all local times. Statistically, the diurnal variation of the F region T/sub e/ signature and the plasmapause at altitudes of the order of 10/sup 4/ km are essentially identical between 2200 and 1300 LT, but they diverge in the afternoon sector. The quiet time T/sub e/ signature remains in the vicinity of 60/sup 0/ at all local times, while the plasmapause itself bulges to about 70/sup 0/ at 1500 LT. Simultaneous DE-1 observations, however, show that the plasmasphere in the bulge region often exhibits an internal feature in the vicinity of 60/sup 0/, which takes the form of a sharp gradient in H/sup +/

• Research Organization: NASA Goddard Space Flight Center, Greenbelt, Maryland
• OSTI ID: 5162072
• Journal Information: J. Geophys. Res.; (United States), Vol. 93:A3
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
F REGION
ELECTRON TEMPERATURE
PLASMAPAUSE
DAILY VARIATIONS
ELECTRON DENSITY
EXPLORER SATELLITES
PLASMA HEATING
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
HEATING
IONOSPHERE
PLANETARY IONOSPHERES
SATELLITES
VARIATIONS
640201* - Atmospheric Physics- Auroral
Ionospheric
& Magetospheric Phenomena