Identification of Presolar Spinel Grains from a Murray Residue by Multi-detection Raster Imaging
نویسندگان
چکیده
Introduction: Grain size separate CG from the Murray CM2 carbonaceous chondrite contains mostly spinel grains of average diameter 0.5 μm [1]. Zinner et al. [2] found that approximately 1% of these spinel grains are of presolar origin as determined by their large O isotopic anomalies. These O isotopic measurements were made with the NanoSIMS on individual grains that were well separated from one another on a gold foil. The grains were selected for analysis from secondary electron and secondary O images. The primary beam was then successively deflected onto these single grains for O isotopic analysis.
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