Medium-Energy Particle Experiments - Electron Analyzer, MEP-e


Measurement Principle

The electrostatic analyzer measures the energy and direction of incoming electrons. Avalanche photodiodes (APDs) are used as detectors. The energy determined by the electrostatic analyzer and the pulse height measured by the APDs are compared to eliminate background noise due to radiation.


Satoshi Kasahara (The University of Tokyo)
Shoichiro Yokota (Osaka University)

Instrument Specifications and Measured Quantities

  • Energy range: <10 to 80 keV
  • Energy resolution: 8% (FWHM)
  • Energy steps: 16 steps per scan
  • Sensor field of view: 360° (azimuth) × 3.5° (elevation)
  • Number of detectors: 16
  • Geometric factor: 6.6×10-5 cm2 sr keV/keV per detector
  • Time resolution: 4 s for full 3-D distribution function