NSSDCA ID: 1978-071A-02
Mission Name: ESA-GEOS 2This instrument (ESA experiment S-302) employed two hemispherical electrostatic analyzers mounted on one of the locking booms for the measurement of electrons or protons over the range 0.5 to 500 eV arriving close to parallel and close to perpendicular to the local magnetic field. The energy range was covered in 64 steps with a relative energy resolution of 0.11. One analyzer had its aperture pointing along the negative Z spin axis, with an opening angle of 18 deg x 18 deg providing a geometric factor (G) of 6E-4 sq cm-sr. The other analyzer made an angle of 100 deg with respect to the +Z axis, with an opening angle of 8 deg x 30 deg, providing a G of 5E-4 sq cm-sr. Both detectors had to measure the same type of particles at the same time. The collimators of these instruments could be set at any voltage from -28 to +32 V in steps of 0.1 V to compensate for the potential difference between the instrument and the undisturbed plasma environment. This voltage was used to determine the spacecraft potential. For additional details, see J. F. E. Johnson et al., Space Sci. Rev., v. 22, p. 567, 1978, and G. L. Wrenn et al., Space Sci. Instrum., v. 5, p. 271, 1981.
Questions and comments about this experiment can be directed to: Dr. H. Kent Hills
Name | Role | Original Affiliation | |
---|---|---|---|
Mr. Keith Norman | Other Investigator | Mullard Space Science Laboratory | |
Sir Robert L. F. Boyd | Other Investigator | University College, London | |
Dr. W. John Raitt | Other Investigator | Utah State University | raitt@cc.usu.edu |
Dr. Gordon L. Wrenn | Principal Investigator | Mullard Space Science Laboratory |