Chemical Properties of the Local Galactic Disk and Halo. I. Fundamental Properties of 1,544 Nearby, High Proper-Motion M dwarfs and subdwarfs

Abstract

Large numbers of low-to-medium resolution spectra of M-type dwarf stars from both the local Galactic disk and halo are available from various surveys. In order to fully exploit these data, we develop a template-fit method using a set of empirically assembled M dwarf/subdwarf classification templates, based on the measurements of the TiO and CaH molecular bands, to classify M dwarfs/subdwarfs by spectral type and metallicity class. We further present a pipeline to automatically determine the effective temperature, metallicity ([M/H]), alpha-element to iron abundance ratio ([alpha/Fe]), and surface gravity of M dwarfs/subdwarfs using the latest version of BT-Settl model atmospheres. We apply these methods to a set of low-to-medium resolution optical spectra of 1,544 high proper-motion (> 0.4"/yr) M dwarfs/subdwarfs. Our metallicity estimates appear to be consistent with the expected color-magnitude variation of stars relative to atmospheric composition, as our sample shows a clear stratification with respect to metallicity in the Gaia H-R diagram. Furthermore, the measured chemical parameters of the two components in 48 binary systems are in a good agreement with each other, which suggest a precision of 0.22 dex in [M/H], 0.08 dex in [alpha/Fe], and 0.16 dex in the combined index [alpha/Fe]+[M/H]. There is also a good consistency between metallicity class, obtained from the empirical classification templates, and the index [alpha/Fe]+[M/H] (~ [alpha/H]), obtained from model-fitting, which means that the more easily measured metallicity class can be used as a relatively reliable indicator of absolute alpha-element abundance, [alpha/H], in low-mass stars. Finally, we examine the distribution of our stars in the [alpha/Fe] vs. [M/H] diagram, which shows evidence of clustering in chemical abundance makeup, suggestive of discrete populations among the local disk and halo stars.

arXiv comment53 pages, 43 figures, 10 tables, accepted for publication in AJ

References in corpus (97)

• Gaia Data Release 2. Summary of the contents and survey properties
• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• SEGUE: A Spectroscopic Survey of 240,000 stars with g=14-20
• Exploring the Milky Way stellar disk. A detailed elemental abundance study of 714 F and G dwarf stars in the Solar neighbourhood
• The Limiting Effects of Dust in Brown Dwarf Model Atmospheres
• Radial Mixing in Galactic Discs
• Models of Stars, Brown Dwarfs and Exoplanets
• Elemental Abundance Survey of The Galactic Thick Disk
• Solar Chemical Abundances Determined with a CO5BOLD 3D Model Atmosphere
• Prevalence of Earth-size planets orbiting Sun-like stars
• Chemical evolution with radial mixing
• A high accuracy computed water line list
• Abundance Gradients and the Formation of the Milky Way
• The Occurrence Rate of Small Planets around Small Stars
• Chemical Cartography with APOGEE: Metallicity Distribution Functions and the Chemical Structure of the Milky Way Disk
• Chemical abundances of 1111 FGK stars from the HARPS GTO planet search program.Galactic stellar populations and planets
• The age structure of stellar populations in the solar vicinity. Clues of a two-phase formation history of the Milky Way disk
• The spatial structure of mono-abundance sub-populations of the Milky Way disk
• Stellar SEDs from 0.3-2.5 Microns: Tracing the Stellar Locus and Searching for Color Outliers in SDSS and 2MASS
• Quantifying the uncertainties of chemical evolution studies. II. Stellar yields
• A Catalog of Northern Stars With Annual Proper Motions Larger Than 0.15 Seconds of Arc (LSPM catalog - North)
• Simulations of stellar convection with CO5BOLD
• Stellar Tidal Streams in Spiral Galaxies of the Local Volume: A Pilot Survey with Modest Aperture Telescopes
• Metallicity and Temperature Indicators in M dwarf K band Spectra: Testing New & Updated Calibrations With Observations of 133 Solar Neighborhood M dwarfs
• The Luminosity and Mass Functions of Low-Mass Stars in the Galactic Disk: II. The Field
• How to Constrain Your M dwarf II: the mass-luminosity-metallicity relation from 0.075 to 0.70$M_{\odot }$
• Origin and structure of the Galactic disc(s)
• M-Subdwarfs: Spectroscopic Classification and the Metallicity Scale
• The Sloan Digital Sky Survey Data Release 7 Spectroscopic M Dwarf Catalog I: Data
• Parallel Implementation of the PHOENIX Generalized Stellar Atmosphere Program
• A revised estimate of the occurrence rate of terrestrial planets in the habitable zones around kepler m-dwarfs
• A Spectroscopic Catalog of the Brightest (J<9) M Dwarfs in the Northern Sky
• An All-Sky Catalog of Bright M Dwarfs
• Red giant masses and ages derived from carbon and nitrogen abundances
• Oxygen Abundances in Nearby FGK Stars and the Galactic Chemical Evolution of the Local Disk and Halo
• The Gaia-ESO Survey: the Galactic Thick to Thin Disc transition
• Near-infrared Metallicities, Radial Velocities and Spectral Types for 447 Nearby M Dwarfs
• An Increase in the Mass of Planetary Systems around Lower-Mass Stars
• Revised metallicity classes for low-mass stars: dwarfs (dM), subdwarfs (sdM), extreme subdwarfs (esdM), and ultra subdwarfs (usdM)
• Formation and Evolution of the Disk System of the Milky Way: [alpha/Fe] Ratios and Kinematics of the SEGUE G-Dwarf Sample
• Chemodynamics of the Milky Way. I. The first year of APOGEE data
• They are Small Worlds After All: Revised Properties of Kepler M Dwarf Stars and their Planets
• M dwarfs: effective temperatures, radii and metallicities
• Prospecting in late-type dwarfs: a calibration of infrared and visible spectroscopic metallicities of late-K and M dwarfs spanning 1.5 dex
• Galactic Archaeology with asteroseismic ages: evidence for delayed gas infall in the formation of the Milky Way disc
• On the Formation of Galactic Thick Disks
• TiO and H${}_2$O absorption lines in cool stellar atmospheres
• Metal-Rich M-dwarf Planet Hosts: Metallicities with K-Band Spectra
• Spectroscopy of New High Proper Motion Stars in the Northern Sky. I. New Nearby Stars, New High Velocity Stars, and an Enhanced Classification Scheme for M Dwarfs
• Kinematics and chemical properties of the Galactic stellar populations. The HARPS FGK dwarfs sample
• Tracing the Galactic thick disk to Solar metallicities
• The SEGUE Stellar Parameter Pipeline. V. Estimation of Alpha-Element Abundance Ratios From Low-Resolution SDSS/SEGUE Stellar Spectra
• A Short Scale Length for the α-Enhanced Thick Disk of the Milky Way: Evidence from Low-Latitude SEGUE Data
• The role of convection, overshoot, and gravity waves for the transport of dust in M dwarf and brown dwarf atmospheres
• Metallicity measurements using atomic lines in M and K dwarf stars
• Numerical simulations of surface convection in a late M-dwarf
• Metallicity of M dwarfs IV. A high-precision [Fe/H] and Teff technique from high-resolution optical spectra for M dwarfs
• Spherically symmetric model atmospheres for low mass pre-Main Sequence stars with effective temperatures between 2000 and 6800 K
• An H-band Spectroscopic Metallicity Calibration for M Dwarfs
• Tidal streams in the Galactic halo: Evidence for the Sagittarius northern stream or traces of a new nearby dwarf galaxy
• M-dwarf metallicities - A high-resolution spectroscopic study in the near infrared
• The metallicity signature of evolved stars with planets
• The Earliest Phases of Galaxy Evolution
• Cool Subdwarf Investigations (CSI) I: New Thoughts for the Spectral Types of K and M Subdwarfs
• Phylogeny of the Milky Way's inner disk and bulge populations: Implications for gas accretion, (the lack of) inside-out thick disk formation, and quenching
• The relationship between mono-abundance and mono-age stellar populations in the Milky Way disk
• Low-mass Binaries in the Hyades - A scarcity of brown dwarfs
• Using the Galactic Dynamics of M7 Dwarfs to Infer the Evolution of Their Magnetic Activity
• Revisiting long-standing puzzles of the Milky Way: the Sun and its vicinity as typical outer disk chemical evolution
• Chemical Abundances of M-dwarfs from the APOGEE Survey. I. The Exoplanet Hosting Stars Kepler-138 and Kepler-186
• Effects of Galactic fountains and delayed mixing in the chemical evolution of the Milky Way
• A high resolution spectroscopic atlas of M subdwarfs - Effective temperature and metallicity
• Radii of 88 M Subdwarfs and Updated Radius Relations for Low-Metallicity M Dwarf Stars
• New High Proper Motion Stars from the Digitized Sky Survey. II. Northern Stars with 0.5<mu<2.0 arcsec/yr at High Galactic Latitudes
• A physically motivated and empirically calibrated method to measure effective temperature, metallicity, and Ti abundance of M dwarfs
• Metallicity determination of M dwarfs - High-resolution IR spectroscopy
• The M Dwarf Problem in the Galaxy
• Metallicity determination of M dwarfs - Expanded parameter range in metallicity and effective temperature
• The physical mechanism behind M dwarf metallicity indicators and the role of C and O abundances
• Variation of Stellar Envelope Convection and Overshoot with Metallicity
• Yule-Simpson's paradox in Galactic Archaeology
• A New Sample of Cool Subdwarfs from SDSS: Properties and Kinematics
• Examining the relationships between colour, $T_{\mathrm{eff}}$, and [M/H] for APOGEE K and M dwarfs
• Automated identification of 2612 late-k and M dwarfs in the LAMOST commissioining data using the classification template fits
• Mapping the Local Halo: Statistical Parallax Analysis of SDSS Low-Mass Subdwarfs
• Milky Way's Thick and Thin disk: Is there distinct thick disk?
• Near Infrared Spectroscopy of M Dwarfs. I. CO Molecule as an Abundance Indicator of Carbon
• The Delay Times of Type Ia Supernova
• Using High-Resolution Optical Spectra to Measure Intrinsic Properties of Low-Mass Stars: New Properties for KOI-314 and GJ 3470
• Near Infrared Spectroscopy of M Dwarfs. II. H2O Molecule as an Abundance Indicator of Oxygen
• Spectral energy distribution of M-subdwarfs: A study of their atmospheric properties
• Optical - Near Infrared Photometric Calibration of M-dwarf Metallicity and Its Application
• Metallicity, temperature, and gravity scales of M subdwarfs
• Probing M subdwarf metallicity with an esdK5+esdM5.5 binary
• A 3D radiative transfer framework: VII. Arbitrary velocity fields in the Eulerian frame
• Near infrared spectroscopy of M dwarfs. IV. A preliminary survey on the carbon isotopic ratios in M dwarfs

Cited by in corpus (15)

• The CARMENES search for exoplanets around M dwarfs. Stellar atmospheric parameters of target stars with SteParSyn
• Elemental abundances of nearby M dwarfs based on high-resolution near-infrared spectra obtained by the Subaru/IRD survey: Proof of concept
• Determination of spectroscopic parameters for 313 M dwarf stars from their APOGEE Data Release 16 H-band spectra
• Stellar Atmospheric Parameters of M-type Stars from LAMOST DR8
• ODUSSEAS: Upgraded version with new reference scale and parameter determinations for 82 planet-host M dwarf stars in SWEET-Cat
• Chemical Properties of the Local Disk and Halo. II. Abundances of 3745 M dwarfs and Subdwarfs from Improved Model Fitting of Low-Resolution Spectra
• Using autoencoders and deep transfer learning to determine the stellar parameters of 286 CARMENES M dwarfs
• Stars in the Local Galactic Thick Disk and Halo in Gaia EDR3: A catalogue of Half a Million Local Main-sequence Stars with Photometric Metallicities
• Bayesian Cross-Matching of High Proper Motion Stars in Gaia DR2 and Photometric Metallicities for $\sim$1.7 million K and M Dwarfs
• M Subdwarf Research. II. Atmospheric Parameters and Kinematics
• Hidden deep in the halo: selection of a reduced proper motion halo catalogue and mining retrograde streams in the velocity space
• The stellar activity-rotation-age relationship under the lens of asteroseismology
• Near-infrared spectroscopic characterisation of Gaia ultra-cool dwarf candidates; Spectral types and peculiarities
• M dwarf spectral indices at moderate resolution: accurate $T_{\mathrm{eff}}$ and [Fe/H] for 178 southern stars
• M Subdwarf Research III. Spectroscopic Diagnostics for Breaking Parameter Degeneracy