Electrodynamics of very-high-latitude arcs in the morning sector auroral zone

Technical Report · Mon Feb 01 04:00:00 EST 1988

OSTI ID:6839738

Robinson, R M; Vondrak, R R; Hardy, D; Gussenhoven, M S; Potemra, T A

An experimental campaign was conducted to study the electrodynamics of auroral arcs at very high latitudes. The experiments involved coordinated observations by radar and two polar-orbiting spacecraft. For several hours around a system of auroral arcs was observed. These arcs varied in intensity and width but were all extended generally in the magnetic east-west direction. A satellite photograph obtained during the observations showed that two types of arcs were present. In the south the arcs were localized enhancements or striations within a broad diffuse aurora. Poleward of the diffuse aurora was a system of arc segments that extended over about 5 deg of latitude. The radar measured enhanced ionospheric electron densities associated with each of these arcs, although the altitudes of the enhancements were different for the two types. In the diffuse aurora the ionization peaked at altitudes near 115 km, whereas in the arc segments the ionization peaked at altitudes above 180 km. Examination of electric field data from the radar indicated that the boundary in ionization associated with the two types of aurora occurred where the southward electric field maximized. The HILAT satellite passed in the vicinity of Sondrestrom during the experiment and measured precipitating-electron fluxes and field-aligned currents.

• Research Organization: Air Force Geophysics Lab., Hanscom AFB, MA (USA)
• OSTI ID: 6839738
• Report Number(s): AD-A-193381/1/XAB; AFGL-TR-88-0069
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALIGNMENT
AURORAL OVAL
CURRENTS
DIFFUSION
EARTH ATMOSPHERE
ELECTRIC FIELDS
ELECTRODYNAMICS
ELECTRON DENSITY
GEOGRAPHICAL VARIATIONS
IONIZATION
IONOSPHERE
LATITUDE EFFECT
MAGNETIC FIELDS
MEASURING INSTRUMENTS
PLANETARY IONOSPHERES
POLAR REGIONS
RADAR
RANGE FINDERS
STRIATIONS
VARIATIONS