2021/05/04 by Diogo Souto, Katia Cunha, Kátia Cunha +2
Physics and Astronomy · #Astro and Planetary Science #Astronomical and nuclear sciences #Astronomy #Astrophysics #Coma (optics) #Metallicity #Open cluster #Physics #Spectral line #Stars #Stellar, planetary, and galactic studies #astro-ph.GA #astro-ph.SR
paper · pdf · doi:10.3847/1538-4357/abfdb5
Accepted to ApJ
arxiv created 2021/05/04 · openalex created_date 2021/05/10 · openalex publication_date 2021/08/01 · arxiv updated 2021/08/18 · openalex updated_date 2026/08/05
Abstract We present a study of metallicities in a sample of main-sequence stars with spectral types M , K , G , and F ( T eff ∼3200–6500K and log g ∼ 4.3–5.0 dex) belonging to the solar neighborhood young open cluster Coma Berenices. Metallicities were determined using the high-resolution ( R = λ /Δ λ ∼ 22,500) NIR spectra ( λ 1.51– λ 1.69 μ m) of the Sloan Digital Sky Survey IV APOGEE survey. Membership to the cluster was confirmed using previous studies in the literature along with APOGEE radial velocities and Gaia DR2. An LTE analysis using plane-parallel MARCS model atmospheres and the APOGEE DR16 line list was adopted to compute synthetic spectra and derive atmospheric parameters ( T eff and log g ) for the M dwarfs and metallicities for the sample. The derived metallicities are near-solar and are homogeneous at the level of the expected uncertainties, in particular when considering stars from a given stellar class. The mean metallicity computed for the sample of G, K , and M dwarfs is 〈[Fe/H]〉 = +0.04 ± 0.02 dex; however, the metallicities of the F -type stars are slightly lower, by about 0.04 dex, when compared to cooler and less massive members. Models of atomic diffusion can explain this modest abundance dip for the F dwarfs, indicating that atomic diffusion operates in Coma Berenices stars. The [Fe/H] dip occurs in nearly the same effective temperature range as that found in previous analyses of the lithium and beryllium abundances in Coma Berenices.