The detection of ultra-relativistic electrons in low Earth orbit

Journal of Space Weather and Space Climate

关键词: ionosphere;    ultra-relativistic electrons;    low Earth orbit;    geostatic orbit;    LYRA;    PROBA2;    VLF/ELF waves;    ECH waves;    EMIC waves;    microbursts;    monoenergetic electrons;   

DOI  :  10.1051/swsc/2017041

来源: DOAJ

【 摘 要 】

Aims. To better understand the radiation environment in low Earth orbit (LEO), the analysis of in-situ observations of a variety of particles, at different atmospheric heights, and in a wide range of energies, is needed. Methods. We present an analysis of energetic particles, indirectly detected by the large yield radiometer (LYRA) instrument on board ESA's project for on-board autonomy 2 (PROBA2) satellite as background signal. Combining energetic particle telescope (EPT) observations with LYRA data for an overlapping period of time, we identified these particles as electrons with an energy range of 2 to 8 MeV. Results. The observed events are strongly correlated to geo-magnetic activity and appear even during modest disturbances. They are also well confined geographically within the L = 4–6 McIlwain zone, which makes it possible to identify their source. Conclusions. Although highly energetic particles are commonly perturbing data acquisition of space instruments, we show in this work that ultra-relativistic electrons with energies in the range of 2–8 MeV are detected only at high latitudes, while not present in the South Atlantic Anomaly region.

【 授权许可】

Unknown