{
  "id": "2001.05597",
  "version": "v1",
  "published": "2020-01-16T00:11:56.000Z",
  "updated": "2020-01-16T00:11:56.000Z",
  "title": "Stellar Characterization of M-dwarfs from the APOGEE Survey: A Calibrator Sample for the M-dwarf Metallicities",
  "authors": [
    "Diogo Souto",
    "Katia Cunha",
    "Verne V. Smith",
    "C. Allende Prieto",
    "Adam Burgasser",
    "Kevin Covey",
    "D. A. Garcia-Hernandez",
    "Jon A. Holtzman",
    "Jennifer A. Johnson",
    "Henrik Jonsson",
    "Suvrath Mahadevan",
    "Steven R. Majewski",
    "Thomas Masseron",
    "Matthew Shetrone",
    "Barbara Rojas-Ayala",
    "Jennifer Sobeck",
    "Keivan G. Stassun",
    "Ryan Terrien",
    "Johanna Teske",
    "Fabio Wanderley",
    "Olga Zamora"
  ],
  "comment": "Accepted to ApJ, 2 tables and 11 figures",
  "categories": [
    "astro-ph.SR",
    "astro-ph.EP",
    "astro-ph.GA"
  ],
  "abstract": "We present spectroscopic determinations of the effective temperatures, surface gravities and metallicities for 21 M-dwarfs observed at high-resolution (R $\\sim$ 22,500) in the \\textit{H}-band as part of the SDSS-IV APOGEE survey. The atmospheric parameters and metallicities are derived from spectral syntheses with 1-D LTE plane parallel MARCS models and the APOGEE atomic/molecular line list, together with up-to-date H$_{2}$O and FeH molecular line lists. Our sample range in $T_{\\rm eff}$ from $\\sim$ 3200 to 3800K, where eleven stars are in binary systems with a warmer (FGK) primary, while the other 10 M-dwarfs have interferometric radii in the literature. We define an $M_{K_{S}}$--Radius calibration based on our M-dwarf radii derived from the detailed analysis of APOGEE spectra and Gaia DR2 distances, as well as a mass-radius relation using the spectroscopically-derived surface gravities. A comparison of the derived radii with interferometric values from the literature finds that the spectroscopic radii are slightly offset towards smaller values, with $\\Delta$ = -0.01 $\\pm$ 0.02 $R{\\star}$/$R_{\\odot}$. In addition, the derived M-dwarf masses based upon the radii and surface gravities tend to be slightly smaller (by $\\sim$5-10\\%) than masses derived for M-dwarf members of eclipsing binary systems for a given stellar radius. The metallicities derived for the 11 M-dwarfs in binary systems, compared to metallicities obtained for their hotter FGK main-sequence primary stars from the literature, shows excellent agreement, with a mean difference of [Fe/H](M-dwarf - FGK primary) = +0.04 $\\pm$ 0.18 dex, confirming the APOGEE metallicity scale derived here for M-dwarfs.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-01-16T00:11:56.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "metallicity",
      "apogee survey",
      "stellar characterization",
      "calibrator sample",
      "m-dwarf metallicities"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}