Electron Microburst Precipitation in Earth’s Magnetosphere

Intense bursts of precipitating electrons called "microbursts" were first detected in the 10-100 keV energy range using balloon-based instrumentation [ Anderson and Milton, 1964 ]. The balloon-borne detectors measure bremsstrahlung x-rays produced by energetic electrons that are scattered into Earth’s atmosphere from the Van Allen radiation belts. Direct low-altitude satellite observations of the precipitating electrons revealed that microbursts can extend up to relativistic energies [e.g, Imhof et al., 1992 , Blake et al., 1996 ] and may be a major loss process for trapped radiation belt electrons [ O’Brien et al., 2004 ].