Japan Geoscience Union Meeting 2018

Presentation information

[EE] Evening Poster

P (Space and Planetary Sciences) » P-EM Solar-Terrestrial Sciences, Space Electromagnetism & Space Environment

[P-EM16] Dynamics of Earth's Inner Magnetosphere and Initial Results from Arase

Tue. May 22, 2018 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Danny Summers(Memorial University of Newfoundland), Yoshizumi Miyoshi(Institute for Space-Earth Environmental Research, Nagoya University), Keisuke Hosokawa(電気通信大学大学院情報理工学研究科, 共同), Yusuke Ebihara(Research Institute for Sustainable Humanosphere, Kyoto University)

[PEM16-P24] Spatial distribution of radiation belt protons deduced from unexpected output of HEP on board the Arase satellite

*Wataru Miyake1, Honoka Toda1, Takefumi Mitani2, Takeshi Takashima2, Yoshizumi Miyoshi3 (1.Tokai University, 2.ISAS/JAXA, 3.ISEE/Nagoya University)

Keywords:proton radiation belt, Arase satellite

HEP instrument on board the Arase satellite measures electrons with energies from 70 keV to 2 MeV. The Van Allen probes observation revealed that the electrons of MeV energy range never exist in the inner radiation belt. However, the HEP has detected unexpected counts even at the 2 MeV energy channel in the inner radiation belt (L < 2.0). Any contamination of high energy protons (> 30 MeV) is supposed to result in the unexpected counts. By assuming no contribution from electrons, we can obtain spatial distribution of energetic protons from the unexpected counts. The result shows a concentration on the magnetic equator especially at L > 1.5, which is basically consistent with pitch angle observation of tens of MeV protons near the magnetic equator from the Van Allen probes.