Articles | Volume 23, issue 3
Ann. Geophys., 23, 931–943, 2005
Ann. Geophys., 23, 931–943, 2005

  30 Mar 2005

30 Mar 2005

A corrector for spacecraft calculated electron moments

J. Geach1,2, S. J. Schwartz1,3, V. Génot4, O. Moullard1, A. Lahiff5, and A. N. Fazakerley5 J. Geach et al.
  • 1Space Plasma Group, Astronomy Unit, Queen Mary, University of London, Mile End Road, London E1 4NS, UK
  • 2now at: Department of Physics, University of Durham, Durham DH1 3HP, UK
  • 3now at: Space and Atmospheric Physics, Blackett Laboratory, Imperial College London, London SW7 2AZ, UK
  • 4Centre d’Etude Spatiale des Rayonnements, 9 Avenue du Colonel Roche, Boite Postale 4346 31028, Toulouse, France
  • 5Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT, UK

Abstract. We present the application of a numerical method to correct electron moments calculated on-board spacecraft from the effects of potential broadening and energy range truncation. Assuming a shape for the natural distribution of the ambient plasma and employing the scalar approximation, the on-board moments can be represented as non-linear integral functions of the underlying distribution. We have implemented an algorithm which inverts this system successfully over a wide range of parameters for an assumed underlying drifting Maxwellian distribution. The outputs of the solver are the corrected electron plasma temperature Te, density Ne and velocity vector Ve. We also make an estimation of the temperature anisotropy A of the distribution. We present corrected moment data from Cluster's PEACE experiment for a range of plasma environments and make comparisons with electron and ion data from other Cluster instruments, as well as the equivalent ground-based calculations using full 3-D distribution PEACE telemetry.