OBSERVATIONS OF AN UPWARD-DIRECTED ELECTRON-BEAM WITH THE PERPENDICULAR TEMPERATURE OF THE COLD IONOSPHERE

Academic Article

Abstract

  • The Freja TESP electron spectrometer has repeatedly observed ∼100 eV ‐ 1 keV upward‐directed, anti‐field‐aligned electron beams near 1700 km altitude in the auroral zone. A particularly intense event, at energies up to 2 keV, is described. The beam perpendicular temperature Te was as low as 0.1–0.2 eV at 100–200 eV parallel energy. The 10–15 s period of upward fluxes was coincident with a low density (∼10 cm−3) period and a ∼5 keV ion conic. Strong low frequency waves and the lack of any downward motion in the simultaneously observed ion conic suggest a strong element of wave acceleration, while electric field and ion loss cone measurements provide limited evidence of potential acceleration to a fraction of the observed energies.
  • Authors

  • BOEHM, MH
  • Clemmons, James
  • WAHLUND, JE
  • ERIKSSON, A
  • ELIASSON, L
  • BLOMBERG, L
  • KINTNER, P
  • HOFNER, H
  • Status

    Publication Date

  • August 15, 1995
  • Published In

    Digital Object Identifier (doi)

    Start Page

  • 2103
  • End Page

  • 2106
  • Volume

  • 22
  • Issue

  • 16