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High-Resolution Abundance Analysis of Very Metal-Rich Stars in the Solar Neighborhood

S. Castro·R. M. Rich·M. Grenon·B. Barbuy·J. K. McCarthy
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Abstract

We report detailed analysis of high-resolution spectra of nine high velocity metal-rich dwarfs in the solar neighborhood. The stars are super metal-rich and 5 of them have [Fe/H]>=+0.4, making them the most metal-rich stars currently known. We find that alpha-elements decrease with increasing metallicity; s-elements are underabundant by about [s-elements/Fe]=-0.3. While exceeding the [Fe/H] of current bulge samples, the chemistry of these stars has important similarities and differences. The near-solar abundances of the alpha-capture elements places these stars on the metal-rich extension of McWilliam & Rich (1994) [ApJS, 91, 749], but their s-process abundances are much lower than those of the bulge giants. These low s-process values have been interpreted as the hallmark of an ancient stellar population.

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S. Castro, R. M. Rich, M. Grenon, B. Barbuy, J. K. McCarthy. 1997-04-22. High-Resolution Abundance Analysis of Very Metal-Rich Stars in the Solar Neighborhood. https://doi.org/10.1086/118481

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