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Derivation of parameters for 3748 FGK stars using H-band spectra from APOGEE Data Release 14

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 نشر من قبل Pedro Sarmento
 تاريخ النشر 2020
  مجال البحث فيزياء
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The Apache Point Observatory Galactic Evolution Experiment (APOGEE) has observed the H-band spectra of over 200 000 stars with $Rsim22 000$. The main motivation for this work is to test an alternative method to the standard APOGEE pipeline (APOGEE Stellar Parameter and Chemical Abundances Pipeline, ASPCAP) to derive parameters in the Near-InfraRed (NIR) for FGK dwarfs. textit{iSpec} and textit{Turbospectrum} are used to generate synthetic spectra matching APOGEE observations and to determine the parameters through $chi^2$ minimization. We present spectroscopic parameters ($T_mathrm{eff}$, $[M/H]$, $log g$, $v_{mic}$) for a sample of 3748 main-sequence and subgiant FGK stars, obtained from their APOGEE H-band spectra We compare our output parameters with the ones obtained with ASPCAP for the same stellar spectra, and find that the values agree within the expected uncertainties. A comparison with the optical samples California Planet Survey, HARPS-GTO (High Accuracy Radial Velocity Planet Searcher - Guaranteed Time Observations), and PASTEL, is also available, and median differences below 10 K for $T_mathrm{eff}$ and 0.2 dex for $[M/H]$ are found. Reasons for these differences are explored. The full H-band line-list, the line selection for the synthesis and the synthesized spectra are available for download, as well as the calculated parameters and their estimated uncertainties.



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