Resonant scattering of energetic electrons by unusual low-frequency hiss

Abstract

We quantify the resonant scattering effects of the unusual low-frequency dawnside plasmaspheric hiss observed on 30 September 2012 by the Van Allen Probes. In contrast to normal (∼100-2000 Hz) hiss emissions, this unusual hiss event contained most of its wave power at ∼20-200 Hz. Compared to the scattering by normal hiss, the unusual hiss scattering speeds up the loss of ∼50-200 keV electrons and produces more pronounced pancake distributions of ∼50-100 keV electrons. It is demonstrated that such unusual low-frequency hiss, even with a duration of a couple of hours, plays a particularly important role in the decay and loss process of energetic electrons, resulting in shorter electron lifetimes for ∼50-400 keV electrons than normal hiss, and should be carefully incorporated into global modeling of radiation belt electron dynamics during periods of intense injections. © 2014. American Geophysical Union. All Rights Reserved.