Medium-energy particle experiments–ion mass analyzer (MEP-i) onboard ERG (Arase)

• Main Authors: Shoichiro Yokota, Satoshi Kasahara, Takefumi Mitani, Kazushi Asamura, Masafumi Hirahara, Takeshi Takashima, Kazuhiro Yamamoto, Yasuko Shibano
• Format: Article
• Language: English
• Published: SpringerOpen 2017-12-01
• Series: Earth, Planets and Space
• Subjects: ERG; Radiation belts; Medium-energy particles; Mass analyses
• Online Access: http://link.springer.com/article/10.1186/s40623-017-0754-8
• ISSN: 1880-5981

Abstract The medium-energy particle experiments–ion mass analyzer (MEP-i) was developed for the exploration of energization and radiation in geospace (ERG) mission (Arase), in order to measure the three-dimensional distribution functions of the inner-magnetospheric ions in the medium energy range between 10 and 180 keV/q. The energy, mass, and charge state of each ion are determined by a combination of an electrostatic energy/charge analyzer, a time-of-flight mass/charge analyzer, and energy-sensitive solid-state detectors. This paper describes the instrumentation of the MEP-i, data products, and observation results during a magnetic storm.