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Title: Red giant stars from the Sloan digital sky survey. II. Distances

We present distance determinations for a large and clean sample of red giant branch stars selected from the ninth data release of the Sloan Digital Sky Survey. The distances are calculated based on both observational cluster fiducials and theoretical isochrones. Distributions of distances from the two methods are very similar with peaks at about 10 kpc and tails extending to more than 70 kpc. We find that distances from the two methods agree well for the majority of the sample stars; though, on average, distances based on isochrones are 10% higher than those based on fiducials. We test the accuracy of our distance determinations using 332 stars from 10 Galactic globular and open clusters. The average relative deviation from the literature cluster distances is 4% for the fiducial-based distances and 8% for the isochrone-based distances, both of which are within the uncertainties. We find that the effective temperature and surface gravity derived from low-resolution spectra are not accurate enough to essentially improve the performance of distance determinations. However, for stars with significant extinction, effective temperature may help to better constrain their distances to some extent. We make our sample stars and their distances available from an online catalog. The catalogmore » comprises 17,941 stars with reasonable distance estimations reaching to more than 70 kpc, which is suitable for the investigation of the formation and evolution of the Galaxy, especially the Galactic halo.« less
Authors:
; ; ; ;  [1]
  1. Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)
Publication Date:
OSTI Identifier:
22370458
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 794; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; CATALOGS; DISTANCE; DISTRIBUTION; EVOLUTION; GALAXIES; GRAVITATION; PEAKS; RED GIANT STARS; RESOLUTION; SPECTRA; SURFACES