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Atypical magnesium abundances in oxygen-rich
stardust: NanoSIMS and Auger analyses.
Vollmer C., Stadermann F. J., Floss C., Hoppe P., and
Brenker F. E. (2008)
71st Meteoritical Society Meeting, Abstract #5054.
ABSTRACT
Astronomical observations indicate that silicates are the
major dust component of O-rich red giant stars. The Mg/Si
and Mg/Fe abundance ratios in these circumstellar shells are
of particular interest, as they strongly influence the types
of dust to condense. These data can be tested on Earth by
high precision laboratory analyses of presolar silicates
found within primitive Solar System materials. Auger
spectroscopy is a powerful tool to study the chemistry of
these stardust grains on a <30 nm scale. It has been used
to analyze rare presolar grain types and also allows
characterization of composite phases. Here we report on
results from combined NanoSIMS/Auger measurements on O-rich
stardust from the Acfer 094 meteorite.
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