Cool Stars 14 - Submitted Abstract # 36
This version created on 05 October 2006

Neon Lights Up a Controversy:  the Solar Ne/O Abundance


Joan Schmelz, University of Memphis

The standard solar model was so reliable that it could predict the
existence of the massive neutrino.  Helioseismology measurements were
so precise that they could determine the depth of the convection zone.
This agreement between theory and observation was the envy of all
astrophysics -- until recently when sophisticated three-dimensional
hydrodynamic calculations of the solar atmosphere reduced the metal
content by a factor of almost two.  Antia & Basu (2005) suggested that
a higher value of the solar neon abundance, Ne/O = 0.52, would resolve
this controversy.  Drake & Testa (2005) presented evidence in favor of
this idea from a sample of 21 Chandra stars with enhanced values of
the neon abundance, Ne/O = 0.41.  We have analyzed solar active region
spectra from the archive of the Flat Crystal Spectrometer on Solar
Maximum Mission, a NASA mission from the 1980s, as well as full-Sun
spectra from the pioneering days of X-ray astronomy in the 1960s.
These data are consistent with the standard neon-to-oxygen abundance
value, Ne/O = 0.15 (Grevesse & Sauval 1998).  We conclude, therefore,
that the enhanced-neon hypothesis will not resolve the current
controversy.

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