July 12, 2016

SWEA instrument

(Solar Wind Electron analyzer)

SWEA instrument drawing
SWEA instrument drawing
SWEA in the vacuum chamber at IRAP for functional tests (engineering model) - © IRAP
SWEA in the vacuum chamber at IRAP for functional tests (engineering model) - © IRAP

The instrument's scientific objectives:

  • Electron impact ionization rate
  • Magnetic field topology (with MAG)
  • Plasma regime
  • Photoelectron energy spectra
  • Auroral electron features
  • Solar wind interaction with Mars (with MAG, SWIA, STATIC, SEP, LPW)

Measurements of the instrument:

  • Energy and angular distributions of solar wind and magnetosheath electrons and ionospheric photoelectrons:
    0 – 3 keV (full angle range)
    3 – 6 keV (limited angle range)

    • Continuous measurements throughout the orbit with 10-sec (20-40 km) resolution to resolve magnetic cusps and bow shock.

    Instrument Accommodation:

    • Large field of view with minimal obstructions
    • Conducting grounded surfaces in the field of view
    • Sensor head in shadow (electronics box sunlit)
    • Simultaneous magnetic field measurements

    The instrument in a few figures

    • Mass 1.4 kg
    • Power 1 Watt
    • Energy range 5 eV - 6 keV
    • Energy resolution 11% (E/E)
    • Field of view 360° × 130°
    • Angular resolution 22.5° × 7°
    • Geom. factor 0.01 cm² ster

    Cut through SWEA instument
    Cross-section of the SWEA instument
    Part of SWEA instrument - © IRAP
    Part of the SWEA instrument - © IRAP