3-D elemental and isotopic composition of presolar silicon carbides
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CitationHenkel, T., Stephan, T., Jessberger, E. K., Hoppe, P., Strebel, R., Amari, S., & Lewis, R. S. (2007). 3‐D elemental and isotopic composition of presolar silicon carbides. Meteoritics & Planetary Science, 42(7-8), 1121-1134.
PublisherThe Meteoritical Society
JournalMeteoritics & Planetary Science
AbstractThirteen presolar silicon carbide grains—three of supernova (SN) origin and ten of asymptotic giant branch (AGB) star origin—were examined with time-of-flightsecondary ion mass spectrometry (TOF-SIMS). The grains had been extracted from two different meteorites—Murchison and Tieschitz—using different acid residue methods. At high lateral resolution of ~300 nm, isotopic and elemental heterogeneities within the micrometer-sized grains were detected. The trace elemental abundances, when displayed in two-element correlation plots, of Li, Mg, K, and Ca show a clear distinction between the two different meteoritic sources. The different concentrations might be attributed to differences of the host meteorites and/or of extraction methods whereas the stellar source seems to be less decisive. In one SN grain with 26Mg-enrichment from extinct 26Al, the acid treatment, as part of the grain separation procedure, affected the Mg/Al ratio in the outer rim and therefore the inferred initial 26Al/27Al ratio. A second SN grain exhibits a lateral heterogeneity in 26Al/27Al, which either is due to residual Al-rich contamination on the grain surface or to the condensation chemistry in the SN ejecta.