Electric-fields derived from electron-drift measurements

• The first observations of electric fields derived from electron E x B drift measurements aboard the Freja spacecraft are presented. The instrument injects a weak beam of 3 keV electrons and measures the displacement of the returning electrons after one gyroperiod. After removing effects due to beam-detector geometry and applying an empirical calibration based upon comparison with the computed v x B electric field induced by the spacecraft motion, good agreement is found when the electron drift measurements are compared with the electric field components measured by the double probe experiment. Examples are presented in which moderately large electric fields are observed near the edges of or adjacent to electron precipitation regions with little or no electric field within.

Subject headings

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Geofysik (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Geophysics (hsv//eng)

Publication and Content Type

ref (subject category)

art (subject category)