Presentation #115.02 in the session Sun-to-Earth Campaign-style Study of Large Space Weather Events — Poster Session.
We use measurements from the NASA Van Allen Probes mission to analyze the response of energetic (tens to hundreds of keV) electrons in the inner radiation belt and below during the large geomagnetic storm of September 2017. High energy resolution flux measurements show evidence of energetic electron injections below the inner belt (i.e., below the stable trapping region, at L < 1.2) on September 7, concurrent with “zebra stripe” patterns in energetic electron spectrograms in the inner belt. The measured flux variations are leveraged to quantify radial transport and to provide complementary information on electric field dynamics. We also present evidence of drift loss cone and bounce loss cone filling below the inner belt, suggesting disturbance electric fields as a source of energetic particle precipitation in the low latitude ionosphere.