Association of Field-Aligned Currents with Small-Scale Auroral Phenomena
- Thomas A. Potemra
Published Online: 21 MAR 2013
Copyright 1984 by the American Geophysical Union.
How to Cite
Cattell, C. (1984) Association of Field-Aligned Currents with Small-Scale Auroral Phenomena, in Magnetospheric Currents (ed T. A. Potemra), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM028p0304
- Published Online: 21 MAR 2013
- Published Print: 1 JAN 1984
Print ISBN: 9780875900551
Online ISBN: 9781118664131
- Magnetospheric currents—Congresses;
- Plasma instabilities—Congresses
Comparisons of theoretically deduced and experimentally measured properties of the field-aligned current regions to the occurrences of electrostatic shocks, electrostatic ion cyclotron (EIC) waves, ion beams, ion conics, and double layers observed within them can yield useful new information and constraints on which plasma processes may be important. Using statistical studies of data from the S3-3 satellite, it is found that the differences between upward and downward current regions and between Region I and Region II currents can explain many of the observed asymmetries between phenomena observed in the evening and morning auroral zone. Statistical studies also imply that EIC waves are destabilized by upward currents; that EIC waves cannot account for the bulk of the energization which produces conics; that connection of Region I currents to the plasmasheet boundary is consistent with many of the observed properties of electrostatic shocks; and that double layers provide the parallel potential to produce inverted-V precipitation in the evening auroral zone. The parallel electric field distribution associated with electrostatic shocks (which probably produce discrete arcs) is still not fully understood, particularly in the morning auroral zone.