Ground Calibration and In-Flight Performance of the Low Energy Particle Analyzer on FY-4B
Bin Su,
Anqin Chen,
Mohan Liu,
Linggao Kong,
Aibing Zhang,
Zheng Tian,
Bin Liu,
Xinyue Wang,
Wenjing Wang,
Xiaoxin Zhang,
Weiguo Zong,
Xiangzhi Zheng,
Jinsong Wang
Affiliations
Bin Su
National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
Anqin Chen
Key Laboratory of Space Weather, National Satellite Meteorological Center, National Center for Space Weather, China Meteorological Administration, Beijing 100081, China
Mohan Liu
Key Laboratory of Space Weather, National Satellite Meteorological Center, National Center for Space Weather, China Meteorological Administration, Beijing 100081, China
Linggao Kong
National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
Aibing Zhang
National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
Zheng Tian
National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
Bin Liu
National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
Xinyue Wang
National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
Wenjing Wang
National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
Xiaoxin Zhang
Key Laboratory of Space Weather, National Satellite Meteorological Center, National Center for Space Weather, China Meteorological Administration, Beijing 100081, China
Weiguo Zong
Key Laboratory of Space Weather, National Satellite Meteorological Center, National Center for Space Weather, China Meteorological Administration, Beijing 100081, China
Xiangzhi Zheng
National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
Jinsong Wang
Key Laboratory of Space Weather, National Satellite Meteorological Center, National Center for Space Weather, China Meteorological Administration, Beijing 100081, China
The FY-4B satellite is one of the second generation of China’s geosynchronous meteorological satellites aiming at numerical weather forecasts. The space environment monitoring package (SEMP) onboard the FY-4B is a comprehensive instrument package for plasma, high-energy particle, and energetic neutral particle measurements. The low-energy particle analyzer (LEPA) is one of the instruments of the SEMP and consists of two top hat electrostatic analyzers designed for plasma detection. The electron and ion sensors are back-to-back assembled and are integrated to a shared electronic box. It measures the three-dimensional velocity distribution of low-energy electrons and ions on the geosynchronous orbit. In this paper, we present the ground calibration and in-flight performance of the instrument. With the electrostatic deflectors and the cylindrically symmetric structure, the instrument provides high-cadence measurements of electron and ion velocity distributions with a wide field of view (FOV) of 180° by 100°, an angular resolution of 16.7° × 20°, and a broad energy range for both the electrons and ions from tens of eV to above 30 keV, with a 1 s time resolution. The geometric factors of the electron and ion analyzers are 1.1 × 10−3 cm2·sr·eV/eV and 1.4 × 10−3 cm2·sr·eV/eV, respectively, which fulfills the requirements of the low-energy plasma measurement. The LEPA monitored typical space environment disturbance such as geomagnetic storms and successfully recorded the responses of plasma energy fluxes. Satellite surface charging events were measured, with the highest potentials of −2000 V in the shadow period and −500 V in the nonshadow period.
