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arXiv · 0909.1279

The Abundance of Deuterium and He3 in the Solar Wind

Frank Scherb
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Abstract

The relative abundance of deuterium (D) in the solar atmosphere is not known. D is not only destroyed in stars, it is also synthesized in the atmospheres of active stars (Prodanovic & Fields 2003). In several cases, production of D in the sun has been detected when solar flares occur, using both energetic particle measurements (Anglin 1975) and by detection of 2.223 MeV gamma rays emitted by D (Terekhov et al. 1996; Shih et al. 2009). We describe a project to measure the abundance of deuterium in the solar wind, and to monitor its evolution during a several-year period. The instrument consists of two grids, a tritium target, and semiconductor particle detectors. The grids, which are hemispherical and concentric, accelerate the incident solar wind ions using a potential difference on the order of ~80 to 100 kV and concentrate the ions on the tritium target. A fraction of the solar wind deuterons thus accelerated interact with the target to produce 3.6 MeV alpha particles, some of which are recorded by adjacent semiconductor detectors. A similar instrument was successfully tested in space in 1975 in order to observe positive auroral ions in a hydrogen aurora.

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Frank Scherb. 2009-09-07. The Abundance of Deuterium and He3 in the Solar Wind. https://arxiv.org/abs/0909.1279

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