Temporal Variation of Sounding Rocket Langmuir Probe Contamination*
Abstract
A novel technique for removing surface contaminants from a sounding rocket spherical Langmuir probe has been developed in the NRL Space Chamber Laboratory. Contamination layers present on probe surfaces can skew the collected data, resulting in the incorrect determination of plasma parameters. Despite careful cleaning procedures prior to launch, probe surfaces can become coated with layers of adsorbed neutral gas in less than a second when exposed to atmosphere. Our laboratory tests show that by heating the probe from the interior using a small halogen lamp, adsorbed neutral particles can be removed from the probe surface, allowing accurate plasma parameter measurements to be made. We present data indicating the effective times required for decontamination and any subsequent recontamination in the absence of heating under a variety of plasma and neutral gas conditions. *Work supported by ONR.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2002
- Bibcode:
- 2002AGUFMSM51B0526A
- Keywords:
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- 2467 Plasma temperature and density;
- 2494 Instruments and techniques;
- 2794 Instruments and techniques;
- 7831 Laboratory studies;
- 7894 Instruments and techniques