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Title: CALIBRATIONS OF ATMOSPHERIC PARAMETERS OBTAINED FROM THE FIRST YEAR OF SDSS-III APOGEE OBSERVATIONS

The Sloan Digital Sky Survey III (SDSS-III) Apache Point Observatory Galactic Evolution Experiment (APOGEE) is a three-year survey that is collecting 10{sup 5} high-resolution spectra in the near-IR across multiple Galactic populations. To derive stellar parameters and chemical compositions from this massive data set, the APOGEE Stellar Parameters and Chemical Abundances Pipeline (ASPCAP) has been developed. Here, we describe empirical calibrations of stellar parameters presented in the first SDSS-III APOGEE data release (DR10). These calibrations were enabled by observations of 559 stars in 20 globular and open clusters. The cluster observations were supplemented by observations of stars in NASA's Kepler field that have well determined surface gravities from asteroseismic analysis. We discuss the accuracy and precision of the derived stellar parameters, considering especially effective temperature, surface gravity, and metallicity; we also briefly discuss the derived results for the abundances of the α-elements, carbon, and nitrogen. Overall, we find that ASPCAP achieves reasonably accurate results for temperature and metallicity, but suffers from systematic errors in surface gravity. We derive calibration relations that bring the raw ASPCAP results into better agreement with independently determined stellar parameters. The internal scatter of ASPCAP parameters within clusters suggests that metallicities are measured with a precisionmore » better than 0.1 dex, effective temperatures better than 150 K, and surface gravities better than 0.2 dex. The understanding provided by the clusters and Kepler giants on the current accuracy and precision will be invaluable for future improvements of the pipeline.« less
Authors:
;  [1] ;  [2] ; ; ; ;  [3] ;  [4] ;  [5] ;  [6] ; ;  [7] ;  [8] ; ;  [9] ;  [10] ;  [11] ;  [12] ;  [13] ;  [14] more »; « less
  1. Instituto de Astrofísica de Canarias (IAC), E-38200 La Laguna, Tenerife (Spain)
  2. New Mexico State University, Las Cruces, NM 88003 (United States)
  3. Department of Astronomy, University of Virginia, Charlottesville, VA 22904-4325 (United States)
  4. Astrophysics Research Institute, Liverpool John Moores University, Egerton Wharf, Birkenhead, Wirral CH41 1LD (United Kingdom)
  5. Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)
  6. Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349-0059 (United States)
  7. University of Birmingham, School of Physics and Astronomy, Edgbaston, Birmingham B15 2TT (United Kingdom)
  8. Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)
  9. Department of Astronomy, The Ohio State University, Columbus, OH 43210 (United States)
  10. Texas Christian University, Fort Worth, TX 76129 (United States)
  11. Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot, IRFU/SAp, Centre de Saclay, F-91191 Gif-sur-Yvette Cedex (France)
  12. Astronomical Institute ''Anton Pannekoek'', University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands)
  13. Institute for Astronomy, University of Vienna, Türkenschanzstrasse 17, A-1180 Vienna (Austria)
  14. Texas Advanced Computing Center, University of Texas, Austin, TX 78759 (United States)
Publication Date:
OSTI Identifier:
22273281
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 146; Journal Issue: 5; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; ASTRONOMY; ASTROPHYSICS; CALIBRATION; CARBON; CHEMICAL COMPOSITION; GALACTIC EVOLUTION; GIANT STARS; GRAVITATION; NITROGEN; RESOLUTION; STAR CLUSTERS