Shift of the auroral electron precipitation boundaries in the dawn-dusk sector in association with geomagnetic activity and interplanetary magnetic field

Journal Article · Sat Oct 01 04:00:00 EDT 1983 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA088iA10p07967· OSTI ID:6814430

Makita, K; Meng, C; Akasofu, S

On the basis of the auroral precipitating electron data along the dawn-dusk meridian from a Defense Meteorological Satellite Program satellite (DMSP-F2), we show that the electron precipitation region extends poleward, often to the geomagnetic latitudes > or approx. =85/sup 0/ from the average oval location, during quiet periods (namely, during periods of a large positive B/sub z/ component). This result may be interpreted as an indication that only a small amount of geomagnetic flux interconnects with the northward IMF, resulting in a contracted ''open'' region (the polar cap). The control of the location of the poleward boundary by the north-south component of the IMF is also statistically examined. The rate of latitudinal movement is about 0.4/sup 0/ to 0.8/sup 0/ per 1 nT for positive IMF B/sub z/ values and about 0.7/sup 0/ to 1.1/sup 0/D per 1 nT for negative IMF B/sub z/ values. The shift of the equatorward boundary is not obvious, however, for positive IMF B/sub z/ values. As geomagnetic activity increases, both the poleward and equatorward boundaries shift toward lower latitudes. The equatorward shift of the poleward and equatorward boundaries is greater than that of the equatorward boundary, resulting in a thinner electron precipitation region during disturbed periods than during quiet periods.

• Research Organization: Applied Physics Laboratory, The Johns Hopkins University
• OSTI ID: 6814430
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 88:A10; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAL OVAL
CHARGED-PARTICLE PRECIPITATION
EARTH ATMOSPHERE
ELECTRON PRECIPITATION
GEOGRAPHICAL VARIATIONS
GEOMAGNETIC FIELD
INTERPLANETARY MAGNETIC FIELDS
IONOSPHERE
LATITUDE EFFECT
MAGNETIC FIELDS
PLANETARY IONOSPHERES
POLAR CUSP
VARIATIONS