Revisiting the "Perfect Detector Concept": Electron Moments From Thermal Noise Spectroscopy and Other Techniques
Abstract
Space plasma measurements by classical particle spectrometers and Langmuir probes are intrinsically limited by the spacecraft potential. This limitation does not affect passive wave measurements at long wavelengths, since they perform an average over a large plasma volume. Thermal noise spectroscopy is based on a passive measurement of the plasma wave spectrum with a long electric antenna, and yields directly the density and the kinetic temperature of a stable electron velocity distribution. This technique does not suffer of the difficulties in plasma resonance identification that impede some other wave techniques as the resonance sounder and the quadripolar probe, and, contrary to them, does not perturb the other in-board instruments. We summarize the limitations and achievements of different plasma detectors in a variety of planetary and plasma environments, and examine how they might be combined on future missions. Finally, we examine how thermal noise spectroscopy might be implemented on a Solar Probe.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2004
- Bibcode:
- 2004AGUFMSH31A1186M
- Keywords:
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- 7800 SPACE PLASMA PHYSICS;
- 7815 Electrostatic structures;
- 7819 Experimental and mathematical techniques;
- 7855 Spacecraft sheaths;
- wakes;
- charging;
- 7894 Instruments and techniques