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arXiv · 2201.00891

Detailed Chemical Abundances for a Benchmark Sample of M Dwarfs from the APOGEE Survey

Diogo Souto·Katia Cunha·Verne V. Smith·D. A. García-Hernández·Jon A. Holtzman·Henrik Jönsson·Suvrath Mahadevan·Steven R. Majewski·Thomas Masseron·Marc Pinsonneault·Donald P. Schneider·Matthew Shetrone·Keivan G. Stassun·Ryan Terrien·Olga Zamora·Guy S. Stringfellow·Richard R. Lane·Christian Nitschelm·Bárbara Rojas-Ayala
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Abstract

Individual chemical abundances for fourteen elements (C, O, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, and Ni) are derived for a sample of M-dwarfs using high-resolution near-infrared $H$-band spectra from the SDSS-IV/APOGEE survey. The quantitative analysis included synthetic spectra computed with 1-D LTE plane-parallel MARCS models using the APOGEE DR17 line list to determine chemical abundances. The sample consists of eleven M-dwarfs in binary systems with warmer FGK-dwarf primaries and ten measured interferometric angular diameters. To minimize atomic diffusion effects, [X/Fe] ratios are used to compare M-dwarfs in binary systems and literature results for their warmer primary stars, indicating good agreement ($<$0.08 dex) for all studied elements. The mean abundance differences in Primaries-this work M-dwarfs is -0.05$\pm$0.03 dex. It indicates that M-dwarfs in binary systems are a reliable way to calibrate empirical relationships. A comparison with abundance, effective temperature, and surface gravity results from the ASPCAP pipeline (DR16) finds a systematic offset of [M/H], $T_{\rm eff}$, log$g$ = +0.21 dex, -50 K, and 0.30 dex, respectively, although ASPCAP [X/Fe] ratios are generally consistent with this study. The metallicities of the M dwarfs cover the range of [Fe/H] = -0.9 to +0.4 and are used to investigate Galactic chemical evolution via trends of [X/Fe] as a function of [Fe/H]. The behavior of the various elemental abundances [X/Fe] versus [Fe/H] agrees well with the corresponding trends derived from warmer FGK-dwarfs, demonstrating that the APOGEE spectra can be used to Galactic chemical evolution using large samples of selected M-dwarfs.

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Diogo Souto, Katia Cunha, Verne V. Smith, D. A. García-Hernández, Jon A. Holtzman, Henrik Jönsson, Suvrath Mahadevan, Steven R. Majewski, Thomas Masseron, Marc Pinsonneault, Donald P. Schneider, Matthew Shetrone, Keivan G. Stassun, Ryan Terrien, Olga Zamora, Guy S. Stringfellow, Richard R. Lane, Christian Nitschelm, Bárbara Rojas-Ayala. 2022-01-03. Detailed Chemical Abundances for a Benchmark Sample of M Dwarfs from the APOGEE Survey. https://doi.org/10.3847/1538-4357/ac4891

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