Upflowing ionospheric ions in the auroral region

Journal Article · Sun Nov 01 04:00:00 EST 1992 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/92JA01435· OSTI ID:6788136

Lu, G; Reiff, P H; Moore, T E; Heelis, R A ^[1]

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1. High Altitude Observatory, Boulder, CO (United States) Rice Univ., Houston, TX (United States) NASA, Marshall Space Flight Center, Huntsville, AL (United States) Univ. of Texas at Dallas, Richardson (United States)

Observations of upflowing ionospheric ions are obtained nearly simultaneously by DE 1 and DE 2 over the nightside auroral regions. At low altitudes, the mean value of the net upward ion number flux is of the order of 10 exp 9/sq cm per sec. The ionosphere is predominantly O(+), and the flux of ions with energy greater than 5 eV is a very small fraction (less than 1 percent) of the total ion flux. At high altitudes, the upflowing ions are accelerated by a parallel electric field and heated (with characteristic energies of hundreds of electron volts). Comparing upflowing fluxes at high and low altitudes yields an estimated height of the bottom of the auroral acceleration region of 1400-1700 km for the region of peak potential drop. This low-altitude acceleration could either be from a parallel electric field or from perpendicular acceleration. The fluxes at the edges of the arc are mostly H(+) thus implying a higher-altitude base of the acceleration region at the edges where the potential drop is lower. 36 refs.

• OSTI ID: 6788136
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 97; ISSN JGREA2; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

661320* -- Auroral
Ionospheric
& Magnetospheric Phenomena-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAL ZONES
CHARGE EXCHANGE
CHARGED PARTICLES
EARTH ATMOSPHERE
FLUX DENSITY
HYDROGEN IONS
ION DENSITY
IONOSPHERE
IONS
PLANETARY IONOSPHERES