Electro Magnetic Ion Cyclotron Wave-induced Electron Precipitation: Ground-based and Satellite Observations

• Main Authors: Clilverd, M., Rodger, C., Hendry, A., Crack, M., Lozinski, A., Raita, T., Ulich, T., Sauvaud, J.
• Format: Conference Object
• Language: English
• Published: 2023
• Subjects: Antarc*; Antarctica; North Atlantic
• Online Access: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5017727

The study of Electro Magnetic Ion Cyclotron (EMIC) wave-induced electron precipitation has a legacy in early work suggesting EMIC waves could precipitate relativistic electrons. As such, EMIC waves represent a significant loss process for the Outer Radiation Belt, and deposit high energy electron precipitation flux deep into the atmosphere. Here we present an analysis of an example of EMIC-induced electron precipitation observed by two satellites in Low Earth Orbit, combined with EMIC wave signatures in ground-based magnetometers in Finland, and Antarctica. Electron precipitation spectral information is provided by satellite data which considers the energy range of scattered electrons during the potential EMIC wave event. We investigate the high energy resolution DEMETER IDP electron measurements in the 80 keV - 2 MeV range, when the detector was looking into the bounce-loss-cone, i.e., flying over the North Atlantic region. In order to assess the effect of potential proton precipitation contamination of the IDP detector we use nearby POES proton flux measurements, compensating for the IDP protective aluminium foil through a calculation of the attenuation of the proton spectrum using the integrated MULASSIS transport code. Our results are considered in the context of recent work indicating a wide energy range of non-relativistic electron precipitation is present in EMIC-induced precipitation in addition to the relativistic energy electrons suggested from the original theoretical suggestions. Our confirmation of non-relativistic energy ranges in EMIC-induced precipitation events supports the atmospheric chemical modelling analysis undertaken recently which showed that EMIC-induced precipitation is capable of causing notable composition changes.