A search for cool subdwarfs: Stellar parameters for 134 candidates

Abstract

The results of a search for cool subdwarfs are presented. Kinematic (U, V, and W) and stellar parameters (Teff, log g, [Fe/H], and V_t) 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.

31 pages, 10 figures, Accepted for publication in PASP

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• Galactic chemical abundance evolution in the solar neighborhood up to the Iron peak
• Classifying Luyten Stars Using An Optical-Infrared Reduced Proper Motion Diagram
• A search for previously unrecognised metal-poor subdwarfs in the Hipparcos astrometric catalogue

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