ION experiment

This page is a mirror of the ION SADS page available at http://sads.cnes.fr:8010. Besides the information already available on this page, there you can browse the ION QuickLook images.

The ION experiment was designed and built by the Centre d'Etude Spatiale des Rayonnements (CNRS/University of Toulouse, France) and funded by a CNES (French National Space Center) grant. The integration tests were performed jointly with the Space Research Institute, Moscow (IKI).

P.I. to contact for more information

Dr. Jean-Andre Sauvaud

CESR
9 avenue du colonel Roche
31028 Toulouse cedex 4, France
Phone: 33 5 61 55 66 76
Facsimile: 33 5 61 55 67 01
E-mail: sauvaud@cesr.cnes.fr

Description

The ION experiment flown on the Interball-Aurora mission performs simultaneous ion and electron measurements. Two mass spectrometers looking in opposing directions perpendicular to the satellite spin axis, which points toward the sun, measure ions in the mass and energy ranges 1-32 amu and ~ 0 to 14,000 eV. The ion measurements are complemented by simple electron spectrometers performing measurements in the energy range ~10 eV (or 60 eV) to 20,000 eV.

The design of the detector heads of the ION-1 and ION-2 mass spectrometers is based on the principle of the Wien filter, where the mass filtering is performed by crossed electric and magnetic fields. The energy over charge (E/Q) selection is made by a cylindrical electrostatic analyzer placed in front of the filter. At each energy step, the electric field in the magnetic analyzer is programmed in order either to scan 2 or 4 ions (H+, He++, He+, O+).

Two spectrometers, ION3 and 4, measure electron fluxes. They consist of two cylindrical electrostatic analyzer heads and associated electronics.

The ION experiment is working since the end of September 1996. Data are regularly obtained in the cusp, cleft, in the nightside auroral zone showing interesting and newly observed features.

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Fig.1: A cleft pass

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Fig. 2: Ion gaps

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Fig.3: Substorm related injections