Energetic Electrons Below the Inner Radiation Belt

R. S. Selesnick , Yi-Jiun Su , J. -A. Sauvaud (1)

1 IRAP - Institut de recherche en astrophysique et planétologie

Energetic electrons have occasionally been observed with high intensity in the low-latitude quasi-trapping region, below the inner radiation belt, where their intensity is normally low. During magnetic storms in November 2004 and July 2006, electrons reached magnetic drift shells with L<1.1. Data from the IDP electron spectrometer on the DEMETER satellite provide high energy resolution, while multiple NOAA/POES satellites provide local time coverage. After accounting for instrumental effects caused by the high intensity, electron kinetic energy is shown to reach at least 200 keV with generally softer spectra than are normally found in the stable trapping region. Electron injection from the inner belt by an enhanced convection electric field ∼5 mV/m may explain the observations. This could provide remote testing for models of global electrodynamics.

Keywords: radiation belt; electrons; magnetic storm; inner belt; electric field; ionosphere

Domains: Sciences of the Universe [physics]

R. S. Selesnick, Yi-Jiun Su, J. -A. Sauvaud. Energetic Electrons Below the Inner Radiation Belt. Journal of Geophysical Research: Space Physics, 2019, 124, pp.5421-5440. ⟨10.1029/2019JA026718⟩. ⟨insu-03674430⟩