Abundances for metal-poor stars with accurate parallaxes
نویسندگان
چکیده
منابع مشابه
Oxygen Abundances in Metal-poor Stars
We present oxygen abundances derived from both the permitted and forbidden oxygen lines for 55 subgiants and giants with [Fe/H] values between −2.7 and solar with the goal of understanding the discrepancy in the derived abundances. A first attempt, using Teff values from photometric calibrations and surface gravities from luminosities, obtained agreement between the indicators for turn-off star...
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We investigate the debated “sulphur discrepancy” found among metal-poor stars of the Galactic halo with [Fe/H]<−2. This discrepancy stems in part from the use of two different sets of sulphur lines, the very weak triplet at 8694 95 Å and the stronger triplet lines at 9212 9238 Å. For three representative cases of metal-poor dwarf, turnoff and subgiant stars, we argue that the abundances from th...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2003
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20030754