Pulsations Of Precipitating Energetic Electrons : Active Satellite Data

Abstract

We present the patterns of high frequency energetic electron (∼ 20 to ∼ 300 keV) pulsations in middle latitudes, in subauroral and auroral regions, based on low altitude nearly polar orbiting satellite (Intercosmos-24, project ACTIVE) measurements. Two detectors with different orientations allowed the fluxes within and outside the loss cone to be compared. The trapped electrons do not exhibit the strong pulsations observed within the bounce loss cone. The pitch angle diffusion coefficient changes significantly on time scales comparable to or even shorter than the bounce period of electrons. The same is valid for changes of precipitating electron energy spectra. There are indications that both pitch angle and energy diffusion are in operation. VLF emissions at f < 3.5 kHz with a complicated structure are observed simultaneously with the electron pulsations, but there is no clear correlation between waves and particles. 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