Evidence for solar flare rare gases in the Khor Temiki aubrite
It has been suggested that the rnain fraction of the rare gases present in gas-rich meteorites was probably incorporated by the solar wind into the grain surfaces, which later were accreted into the meteorite breccias, and in some experiments on Khor Temiki(a gas-rich aubrite) it was shown that most of the gas was surfacecorrelated and resided in the superficial micron or less, consistent with the range of solar wind ions (0.05 to 0.1 mu m). It has also been shown that there are track-rich'' grains in the dark portions of gas-rich meteorites, as well as the normal grains, and indications were obtained that, in addition to their exposure to solar-wind particles, these track-rich'' grains were exposed to solar-flare particles of energies up to a few MeV/nucleon for ~10/sup 4/ yr before accreting into the meteorite, and there is a correlation between the abundance of track-rich'' grains and the concentration of trapped rare gases. Ilmenite is the most retentive lunar mineral studied; there has been some diffusion loss of He, but little or no diffusion loss of Ne and heavier gases. The Khor Temiki enstatite and pyroxene seem to have suffered less diffusion loss than even the lunar minerals. Estimations are made of the percentage of solar- flare gas relative to solar-wind gas in a 200 mu m grain. If there is no diffusion of solar wind into the grains, the solar-flare gases will become the major remaining component after removal of the top several microns, due to the short range of the solar-wind particles. The Khor Temiki enstatite appears to be an ideal sample in which to look for evidence of solar-flare gases. (UK)
- Research Organization:
- Univ. of California, Berkeley
- NSA Number:
- NSA-29-005877
- OSTI ID:
- 4382602
- Journal Information:
- Nature (London) Phys. Sci., v. 244, no. 138, pp. 122-123, Journal Name: Nature (London) Phys. Sci., v. 244, no. 138, pp. 122-123; ISSN NPSCA
- Country of Publication:
- United Kingdom
- Language:
- English
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