A Search for Cool Subdwarfs: Stellar Parameters for 134 Candidates
نویسنده
چکیده
The results of a search for cool subdwarfs are presented. Kinematic (U, V, and W) and stellar parameters (Teff , log g, [Fe/H], and ξt) are derived for 134 candidate subdwarfs based on high resolution spectra. The observed stars span 4200K < Teff < 6400K and −2.70 < [Fe/H] < 0.25 including only 8 giants (log g < 4.0). Of the sample, 100 stars have MgH bands present in their spectra. The targets were selected by their large reduced proper-motion, the offset from the solar metallicity main sequence, or culled from the literature. We confirm the claims made by Ryan (1989) regarding the NLTT catalog being a rich source of subdwarfs and verify the success of the reduced proper-motion constraint in identifying metal-poor stars. Subject headings: stars: abundances – stars: fundamental parameters – subdwarfs
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Finding Cool Subdwarfs Using a V − J Reduced Proper-motion Diagram: Stellar Parameters for 91 Candidates
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