Viking investigations of auroral electrodynamical processes
- Royal Institute of Technology, Stockholm (Sweden)
Recent results from the Viking electric field experiment and their contribution to a better understanding of the aurora and of associated ionosphere-magnetosphere processes are briefly reviewed. The high-resolution electric field data have provided new and important results in a number of different areas, including auroral electrodynamics both on the arc scale size and on the global scale, the auroral acceleration process, the current-voltage relationship, substorms, and the dynamics of the polar cusp. After a short introduction presenting some of the characteristic features of the high-altitude electric field data the remainder of this paper focuses on the role of the electric field in auroral electrodynamics and in the auroral acceleration process. The relationships between the auroral emissions and the associated electric field, current, particle, and conductivity distributions are discussed for both small-scale and large-scale auroral distributions on the basis of results from Viking event studies and from numerical model studies. Particular attention is paid to ionospheric convection and field- aligned current signatures associated with northward interplanetary magnetic field (IMF) auroral distributions, such as the theta aurora or those characterized by extended auroral activity poleward of the classical auroral oval. The role of dc electric fields for the auroral acceleration process has been further investigated and clarified. Intense low-frequency electric field fluctuations (
- OSTI ID:
- 6820692
- Journal Information:
- Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 98:A2; ISSN JGREA2; ISSN 0148-0227
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
Ionospheric
& Magnetospheric Phenomena-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCELERATION
ADMINISTRATIVE PROCEDURES
AURORAE
AURORAL OVAL
CHARGED PARTICLES
CONFIGURATION
CONVECTION
DYNAMICS
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ELECTRIC FIELDS
ELECTRODYNAMICS
ELECTRONS
ELEMENTARY PARTICLES
ENERGY TRANSFER
FERMIONS
FLUCTUATIONS
FREQUENCY RANGE
HEAT TRANSFER
INVESTIGATIONS
IONOSPHERE
IONS
LEPTONS
MAGNETIC STORMS
MASS TRANSFER
MECHANICS
PLANETARY IONOSPHERES
POLAR CUSP
SIZE
SPACE VEHICLES
VARIATIONS
VEHICLES
VIKING SPACE PROBES