IN-SYNC I: Homogeneous stellar parameters from high-resolution apogee spectra for thousands of pre-main sequence stars

Journal Article · Mon Oct 20 00:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/794/2/125· OSTI ID:22370394

Cottaar, Michiel; Meyer, Michael R. ^[1]; Covey, Kevin R. ^[2]; Nidever, David L. ^[3]; Stassun, Keivan G. ^[4]; Foster, Jonathan B. ^[5]; Tan, Jonathan C.; Da Rio, Nicola ^[6]; Chojnowski, S. Drew; Skrutskie, Michael; Majewski, Steven R.; Wilson, John C.; Zasowski, Gail ^[7]; Flaherty, Kevin M. ^[8]

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1. Institute for Astronomy, ETH Zurich, Wolfgang-Pauli-Strasse 27, 8093 Zurich (Switzerland)
2. Lowell Observatory, Flagstaff, AZ 86001 (United States)
3. Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States)
4. Department of Physics and Astronomy, Vanderbilt University, VU Station B 1807, Nashville, TN 37235 (United States)
5. Yale Center for Astronomy and Astrophysics, Yale University New Haven, CT 06520 (United States)
6. Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States)
7. Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)
8. Astronomy Department, Wesleyan University, Middletown, CT 06459 (United States)

Over two years, 8859 high-resolution H-band spectra of 3493 young (1-10 Myr) stars were gathered by the multi-object spectrograph of the APOGEE project as part of the IN-SYNC ancillary program of the SDSS-III survey. Here we present the forward modeling approach used to derive effective temperatures, surface gravities, radial velocities, rotational velocities, and H-band veiling from these near-infrared spectra. We discuss in detail the statistical and systematic uncertainties in these stellar parameters. In addition, we present accurate extinctions by measuring the E(J – H) of these young stars with respect to the single-star photometric locus in the Pleiades. Finally, we identify an intrinsic stellar radius spread of about 25% for late-type stars in IC 348 using three (nearly) independent measures of stellar radius, namely, the extinction-corrected J-band magnitude, the surface gravity, and the Rsin i from the rotational velocities and literature rotation periods. We exclude that this spread is caused by uncertainties in the stellar parameters by showing that the three estimators of stellar radius are correlated, so that brighter stars tend to have lower surface gravities and larger Rsin i than fainter stars at the same effective temperature. Tables providing the spectral and photometric parameters for the Pleiades and IC 348 have been provided online.

• OSTI ID: 22370394
• Journal Information: Astrophysical Journal, Vol. 794, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
GRAVITATION
INFRARED SPECTRA
MAIN SEQUENCE STARS
RADIAL VELOCITY
RESOLUTION
ROTATION
SIMULATION
SURFACES