Most high-energy particle injections do not reach geostationary orbit


  • Colin Schultz


The injection of high-energy particles into the inner magnetotail is often considered a reliable sign of a magnetic substorm. These injections are often thought to be caused by flow bursts, short-lived periods of narrow fast flow streams in the magnetotail. Analyzing records of flow bursts at the entry to the night-side inner magnetosphere, from 8 to 13 Earth radii, as seen by Geotail from 1995 to 2005, and by the Time History of Events and Macroscale Interactions During Substorms (THEMIS) satellite from 2008 to 2009, Sergeev et al. found that most flow bursts do not cause the injection of high-energy particles to geostationary altitudes, and thus such injections are a poor measure of substorm activity.