Identical or fraternal twins? : The chemical homogeneity of wide binaries from Gaia DR2

Abstract

One of the high-level goals of Galactic archaeology is chemical tagging of stars across the Milky Way to piece together its assembly history. For this to work, stars born together must be uniquely chemically homogeneous. Wide binary systems are an important laboratory to test this underlying assumption. Here we present the detailed chemical abundance patterns of 50 stars across 25 wide binary systems comprised of main-sequence stars of similar spectral type identified in Gaia DR2 with the aim of quantifying their level of chemical homogeneity. Using high-resolution spectra obtained with McDonald Observatory, we derive stellar atmospheric parameters and precise detailed chemical abundances for light/odd-Z (Li, C, Na, Al, Sc, V, Cu), $\alpha$ (Mg, Si, Ca), Fe-peak (Ti, Cr, Mn, Fe, Co, Ni, Zn), and neutron capture (Sr, Y, Zr, Ba, La, Nd, Eu) elements. Results indicate that 80% (20 pairs) of the systems are homogeneous in [Fe/H] at levels below 0.02 dex. These systems are also chemically homogeneous in all elemental abundances studied, with offsets and dispersions consistent with measurement uncertainties. We also find that wide binary systems are far more chemically homogeneous than random pairings of field stars of similar spectral type. These results indicate that wide binary systems tend to be chemically homogeneous but in some cases they can differ in their detailed elemental abundances at a level of [X/H] ~ 0.10 dex, overall implying chemical tagging in broad strokes can work.

arXiv comment20 pages, 9 Figures, 5 Tables, Accepted for Publication in MNRAS

References in corpus (91)

• 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
• The Apache Point Observatory Galactic Evolution Experiment (APOGEE)
• Nucleosynthesis in Chandrasekhar Mass Models for Type Ia Supernovae and Constraints on Progenitor Systems and Burning-Front Propagation
• Astrophysics Source Code Library
• The New Galaxy: Signatures of its Formation
• Galactic chemical evolution: Carbon through Zinc
• The First Data Release (DR1) of the LAMOST general survey
• The GALAH Survey: Scientific Motivation
• The O-Na and Mg-Al Anticorrelations in Turn-Off and early Subgiants in Globular Clusters
• Determining stellar atmospheric parameters and chemical abundances of FGK stars with iSpec
• The Radial Velocity Experiment (RAVE): Fifth Data Release
• A Search for Stars of Very Low Metal Abundance. VI. Detailed Abundances of 313 Metal-Poor Stars
• Gaia Data Release 2: first stellar parameters from Apsis
• The peculiar solar composition and its possible relation to planet formation
• Spectral Properties of Cool Stars: Extended Abundance Analysis of 1617 Planet Search Stars
• The Most Metal-Poor Stars. II. Chemical Abundances of 190 Metal-Poor Stars Including 10 New Stars With [Fe/H] < -3.5
• Very Wide Binaries and Other Comoving Stellar Companions: A Bayesian Analysis of the Hipparcos Catalogue
• CH in stellar atmospheres: an extensive linelist
• APOGEE Data Releases 13 and 14: Data and Analysis
• The Formation of Low-Mass Binary Star Systems Via Turbulent Fragmentation
• Chemodynamical Simulations of the Milky Way Galaxy
• Wide companions to Hipparcos stars within 67 pc of the Sun
• The Gaia-ESO Survey: radial metallicity gradients and age-metallicity relation of stars in the Milky Way disk
• Formation of the Widest Binaries from Dynamical Unfolding of Triple Systems
• Prospecting in late-type dwarfs: a calibration of infrared and visible spectroscopic metallicities of late-K and M dwarfs spanning 1.5 dex
• Both accurate and precise gf-values for FeII lines
• The formation of very wide binaries during the star cluster dissolution phase
• Metal-Rich M-dwarf Planet Hosts: Metallicities with K-Band Spectra
• Improved Laboratory Transition Probabilities for Neutral Chromium and Re-determination of the Chromium Abundance for the Sun and Three Stars
• The influence of atomic diffusion on stellar ages and chemical tagging
• The End of the MACHO Era: Limits on Halo Dark Matter from Stellar Halo Wide Binaries
• New Distant Companions to Known Nearby Stars. II. Faint companions of Hipparcos stars and the frequency of wide binary systems
• Experimental f-value and isotopic structure for the Ni I line blended with [OI] at 6300A
• Comoving stars in Gaia DR1: An abundance of very wide separation co-moving pairs
• Elemental abundance differences in the 16 Cygni binary system: a signature of gas giant planet formation?
• The chemical homogeneity of open clusters
• Improved Ti II log(gf) Values and Abundance Determinations in the Photospheres of the Metal-Poor Star HD 84937
• Chemical Homogeneity in Collinder 261 and Implications for Chemical Tagging
• Carbon and oxygen abundances in stellar populations
• Imprints of white dwarf recoil in the separation distribution of Gaia wide binaries
• Discovery of an equal-mass "twin" binary population reaching 1000+ AU separations
• Fe I Oscillator Strengths for the Gaia-ESO Survey
• PUSHing Core-Collapse Supernovae to Explosions in Spherical Symmetry III: Nucleosynthesis Yields
• An accurate and self-consistent chemical abundance catalogue for the APOGEE/Kepler sample
• High-precision stellar abundances of the elements - methods and applications
• Abundance differences between components of wide binaries
• Wide Binaries in Tycho-{\it Gaia}: Search Method and the Distribution of Orbital Separations
• Improved Ni I log(gf) Values and Abundance Determinations in the Photospheres of the Sun and Metal-poor Star HD 84937
• The dissimilar chemical composition of the planet-hosting stars of the XO-2 binary system
• Oxygen abundances in low- and high-alpha field halo stars and the discovery of two field stars born in globular clusters
• A Differential Spectroscopic Analysis of 16 Cygni A and B
• The Hyades open cluster is chemically inhomogeneous
• Fe I Oscillator Strengths for Transitions from High-lying Even-Parity Levels
• The formation of permanent soft binaries in dispersing clusters
• Galactic Doppelganger: The chemical similarity among field stars and among stars with a common birth origin
• LAMOST Spectroscopic Survey of the Galactic Anticentre (LSS-GAC): the second release of value-added catalogues
• Kronos & Krios: Evidence for accretion of a massive, rocky planetary system in a comoving pair of solar-type stars
• Signatures of unresolved binaries in stellar spectra: implications for spectral fitting
• Metallicity Fluctuation Statistics in the Interstellar Medium and Young Stars. I. Variance and Correlation
• High precision abundances in the 16 Cyg binary system: a signature of the rocky core in the giant planet
• The wide binary fraction of solar-type stars: emergence of metallicity dependence at a < 200 AU
• Calibrating the metallicity of M dwarfs in wide physical binaries with F-, G-, and K- primaries - I: High-resolution spectroscopy with HERMES: stellar parameters, abundances, and kinematics
• The Curious Case of Elemental Abundance Differences in the Dual Hot Jupiter Hosts WASP-94AB
• Chemical tagging can work: Identification of stellar phase-space structures purely by chemical-abundance similarity
• The GAPS Programme with HARPS-N at TNG. X. Differential abundances in the XO-2 planet hosting binary
• Prospects for chemically tagging stars in the Galaxy
• Signatures of rocky planet engulfment in HAT-P-4. Implications for chemical tagging studies
• The Initial-Final Mass Relation among White Dwarfs in Wide Binaries
• Formation of wide binary stars from adjacent cores
• Characterizing the High-Velocity Stars of RAVE: The Discovery of a Metal-Rich Halo Star Born in the Galactic Disk
• The Solar Twin Planet Search. V. Close-in, low-mass planet candidates and evidence of planet accretion in the solar twin HIP 68468
• Quantitative chemical tagging, stellar ages and the chemo-dynamical evolution of the Galactic disc
• Reaching the boundary between stellar kinematic groups and very wide binaries. III. Sixteen new stars and eight new wide systems in the beta Pictoris moving group
• Time evolution of high-energy emissions of low-mass stars:I. Age determination using stellar chronology with white dwarfs in wide binaries
• The chemical composition of HIP34407/HIP34426 and other twin-star comoving pairs
• Constraints on the Initial-Final Mass Relation from Wide Double White Dwarfs
• The role of binaries in the enrichment of the early Galactic halo. I. r-process-enhanced metal-poor stars
• Formation of Wide Binaries by Turbulent Fragmentation
• Towards precise ages for single stars in the field. Gyrochronology constraints at several Gyr using wide binaries. I. Ages for initial sample
• The Fastest Travel Together: Chemical Tagging of the Fastest Stars in Gaia DR2 to the Stellar Halo
• Using APOGEE Wide Binaries to Test Chemical Tagging with Dwarf Stars
• Precise Ages of Field Stars from White Dwarf Companions
• Wide binaries in ultra-faint galaxies: a window onto dark matter on the smallest scales
• The COMBS survey I: Chemical Origins of Metal-Poor Stars in the Galactic Bulge
• Gaia Assorted Mass Binaries Long Excluded from SLoWPoKES (GAMBLES): Identifying Ultra-Wide Binary Pairs with Components of Diverse Mass
• M Subdwarf Secondaries: A Test of the Metallicity Scale
• Lithium Abundances in Wide Binaries with Solar-Type Twin Components
• The GALAH survey: Co-orbiting stars and chemical tagging
• The impact of pollution on stellar evolution models
• Spectroscopic confirmation of very-wide stellar binaries and large-separation comoving pairs from Gaia DR1

Cited by in corpus (48)

• A million binaries from Gaia eDR3: sample selection and validation of Gaia parallax uncertainties
• A Sun-like star orbiting a black hole
• Gaia Data Release 3: Apsis II -- Stellar Parameters
• A red giant orbiting a black hole
• TESS Hunt for Young and Maturing Exoplanets (THYME) IV: Three small planets orbiting a 120 Myr-old star in the Pisces--Eridanus stream
• Chemical evidence for planetary ingestion in a quarter of Sun-like stars
• A Possible Alignment Between the Orbits of Planetary Systems and their Visual Binary Companions
• Abundances in the Milky Way across five nucleosynthetic channels from 4 million LAMOST stars
• Strong chemical tagging with APOGEE: 21 candidate star clusters that have dissolved across the Milky Way disc
• Distant Relatives: The Chemical Homogeneity of Comoving Pairs Identified in Gaia
• The detailed chemical abundance patterns of accreted halo stars from the optical to infrared
• The non-monotonic, strong metallicity dependence of the wide-binary fraction
• Host-star and exoplanet compositions: a pilot study usinga wide binary with a polluted white dwarf
• Elemental Abundances of M Dwarfs Based on High-Resolution Near-Infrared Spectra: Verification by Binary Systems
• Planet Engulfment Detections are Rare According to Observations and Stellar Modeling
• Planet Engulfment Signatures in Twin Stars
• Detailed elemental abundances of binary stars: Searching for signatures of planet formation and atomic diffusion
• Long-Term Lithium Abundance Signatures following Planetary Engulfment
• The GALAH survey: Chemical homogeneity of the Orion complex
• The Chemical Nature of the Young 120-Myr-old Nearby Pisces-Eridanus Stellar Stream Flowing through the Galactic Disk
• From birth associations to field stars: mapping the small-scale orbit distribution in the Galactic disc
• Characterisation of 92 Southern TESS Candidate Planet Hosts and a New Photometric [Fe/H] Relation for Cool Dwarfs
• Chemical Properties of the Local Disk and Halo. II. Abundances of 3745 M dwarfs and Subdwarfs from Improved Model Fitting of Low-Resolution Spectra
• The consistency of chemical clocks among coeval stars
• Enhancement of Double-Close-Binary Quadruples
• The peculiar chemical pattern of the WASP-160 binary system: signatures of planetary formation and evolution?
• The Stars of the HETDEX Survey. I. Radial Velocities and Metal-Poor Stars from Low-Resolution Stellar Spectra
• Wide binary stars formed in the turbulent interstellar medium
• Spatial and Kinematic Clustering of Stars in the Galactic Disk
• Wide binaries from the H3 survey: the thick disk and halo have similar wide binary fractions
• Long-period eclipsing binaries: towards the true mass-luminosity relation. II. Absolute parameters of the NN Del system
• Cool and Data-Driven: An Exploration of Optical Cool Dwarf Chemistry with Both Data-Driven and Physical Models
• Tidal debris from Omega Centauri discovered with unsupervised machine learning
• Internal calibration of LAMOST and Gaia DR3 GSP-Spec stellar abundances
• Detailed abundances of the wide pairs of stars with and without planets: the binary systems 16 Cyg and HD 219542
• A GALAH View of the Chemical Homogeneity and Ages of Stellar Strings Identified in Gaia
• The Hobby-Eberly Telescope VIRUS Parallel Survey (HETVIPS)
• Dynamical masses across the Hertzsprung-Russell diagram
• Chemodynamics of metal-poor wide binaries in the Galactic halo: Association with the Sequoia event
• Host-star and exoplanet composition: Polluted white dwarf reveals depletion of moderately refractory elements in planetary material
• Assessing stellar yields in Galaxy chemical evolution: observational stellar abundance patterns
• The Solar Neighborhood LII: M Dwarf Twin Binaries -- Presumed Identical Twins Appear Fraternal in Variability, Rotation, H$\alpha$, and X-rays
• Long-period double-lined eclipsing binaries: the system V454 Aur with the secondary eclipse caused by the occultation of the hotter component
• Identifying substructure associations in the Milky Way halo using chemo-kinematic tagging
• The Wanderer: Charting WASP-77A b's Formation and Migration Using a System-Wide Inventory of Carbon and Oxygen Abundances
• Red giant asteroseismic binaries in the Kepler field
• PSF-based Analysis for Detecting Unresolved Wide Binaries
• The eccentricity distribution of wide binaries and their individual measurements