Highly Relativistic Electron Flux Enhancement During the Weak Geomagnetic Storm of April–May 2017

@article{Katsavrias2019HighlyRE,
  title={Highly Relativistic Electron Flux Enhancement During the Weak Geomagnetic Storm of April–May 2017},
  author={Christos Katsavrias and Ingmar Sandberg and Wen Li and Olena Podladchikova and Ioannis A. Daglis and Constantinos Papadimitriou and C. Tsironis and Sigiava Aminalragia-Giamini},
  journal={Journal of Geophysical Research: Space Physics},
  year={2019},
  volume={124},
  pages={4402 - 4413}
}
We report observations of energetic electron flux and phase space density to show that a relatively weak magnetic storm with Sym‐Hmin≈−50 nT, resulted in a relativistic and ultrarelativistic electron enhancement of two orders of magnitude similar to the St. Patrick's event of 2015, an extreme storm with Sym‐Hmin≈−235 nT. This enhancement appeared at energies up to ≈10 MeV, lasted for at least 24 days, and was not recorded in geosynchronous orbit where most space weather alert data are collected… 

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