Near-Earth substorm onset - a coordinated study
1994 (English)In: Geophysical Research Letters, ISSN 0094-8276, Vol. 21, no 17, 1875-1878 p.Article in journal (Refereed) Published
We present simultaneous satellite and ground-based measurements of a substorm. Throughout the initial substorm expansion, southward drifting arcs are observed poleward of the expanding substorm aurora, indicating two independent systems of particle precipitation. Freja passes the brightening onset arc in the topside ionosphere near the moment of the substorm onset, observing an Alfven wave, field aligned current and oxygen ion outflow. The substorm onset occurs at low magnetospheric L-shells, near the poleward edge of the region of trapped particles. The location and time for the substorm injection are confirmed by geostationary spacecraft together with magnetometers, all-sky cameras and radar on the ground. We believe that the substorm onset may be triggered by modification of the oxygen content of the inner magnetosphere during the growth-phase caused by ionospheric ion outflow.
Place, publisher, year, edition, pages
1994. Vol. 21, no 17, 1875-1878 p.
Fusion, Plasma and Space Physics
IdentifiersURN: urn:nbn:se:kth:diva-39284DOI: 10.1029/94GL01426ISI: A1994PC81700034OAI: oai:DiVA.org:kth-39284DiVA: diva2:511082
NR 201408052012-03-192011-09-092012-03-19Bibliographically approved