SM41D-2514
A third radiation zone at relativistic energies observed by SAMPEX HILT during the Bastille Day event

Thursday, 17 December 2015
Poster Hall (Moscone South)
Kyung-Chan Kim, KASI Korea Astronomy and Space Science Institute, Daejeon, South Korea, Yuri Shprits, University of California Los Angeles, Los Angeles, CA, United States and J. Bernard Blake, Aerospace Corporation Los Angeles, Los Angeles, CA, United States
Abstract:
During July 2000 geomagnetic storm, known as the Bastille Day storm, SAMPEX HILT observed a strong injection of ~1 MeV electrons into the inner radiation zone (below 2 RE) during the storm main phase. Then during the recovery phase electrons are clearly diffusing inwards and forming a pronounced split-structure encompassing a narrow newly formed slot region around L=3. SAMPEX observations are first compared with electron and proton observations on NOAA POES and HEO to validate that the observed unusual dynamics is not caused by contamination by protons. In this study, we perform the time-dependent 3D Versatile Electron Radiation Belt (VERB) simulations of 1 MeV electron flux evolution and have compared the results with the SAMPEX HILT observations. The result shows that the overall time evolution of the observed split structure is in a good agreement with our model simulations. We find that this new belt at energy of ~1 MeV is resulted from scattering by plasmaspheric hiss to the Earth’s atmosphere.