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arXiv · 2509.11938

Chemical Abundances of M and G Dwarfs in the Hyades and Coma Berenices Open Clusters from APOGEE Spectra

Deusalete Vilar·Diogo Souto·Katia Cunha·Anderson andrade-silva·Veronica Loaiza-Tucuri·Fabio Wanderley·Verne V. Smith·Vinicius Grilo·Cintia F. Martinez·Barbara Rojas-Ayala·Zachary Way
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Abstract

Open clusters are one of the best astrophysical laboratories we have available for stellar astrophysics studies. This work presents metallicities and individual abundances for fourteen M dwarfs and six G dwarfs from two well-known open clusters: Hyades and Coma Berenices. Our analysis is based on near-infrared (1.51--1.69 $\mu$m), high-resolution ($R \sim 22,500$) spectra obtained from the SDSS IV/APOGEE Survey. Using one-dimensional, plane-parallel MARCS model atmospheres, the APOGEE line list, and the Turbospectrum radiative transfer code in local thermodynamic equilibrium, we derived spectroscopic stellar parameters for the M dwarfs, along with abundances of 13 elements (C, O, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, and Fe) for both M and G dwarfs. We find a high degree of chemical homogeneity within each cluster when comparing abundances derived from M and G dwarfs: $\delta$[M/H] (M dwarfs -- G dwarfs) of 0.01$\pm$0.04, and 0.02$\pm$0.03 for the Hyades and Coma Berenices, respectively. The overall cluster metallicities derived from M dwarfs (Hyades: 0.16$\pm$0.03 and Coma Berenices: 0.02$\pm$0.06) are consistent with previous literature determinations. Finally, we demonstrate the value of M dwarfs as key tracers in galactic archaeology, emphasizing their potential for studying galactic metallicity gradients and chemical evolution.

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Deusalete Vilar, Diogo Souto, Katia Cunha, Anderson andrade-silva, Veronica Loaiza-Tucuri, Fabio Wanderley, Verne V. Smith, Vinicius Grilo, Cintia F. Martinez, Barbara Rojas-Ayala, Zachary Way. 2025-09-15. Chemical Abundances of M and G Dwarfs in the Hyades and Coma Berenices Open Clusters from APOGEE Spectra. https://arxiv.org/abs/2509.11938

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