C3PO: Towards a complete census of co-moving pairs of stars-I. High precision stellar parameters for 250 stars

David Yong; Fan Liu; Yuan Sen Ting; Meridith Joyce; Bertram Bitsch; Fei Dai; Aaron Dotter; Amanda I. Karakas; Michael T. Murphy

doi:10.1093/mnras/stad2679

C3PO: Towards a complete census of co-moving pairs of stars-I. High precision stellar parameters for 250 stars

David Yong, Fan Liu, Yuan Sen Ting, Meridith Joyce, Bertram Bitsch, Fei Dai, Aaron Dotter, Amanda I. Karakas, Michael T. Murphy

School of Physics and Astronomy

Research output: Contribution to journal › Article › Research › peer-review

10 Citations (Scopus)

Abstract

We conduct a line-by-line differential analysis of a sample of 125 co-moving pairs of stars (dwarfs and subgiants near solar metallicity). We obtain high-precision stellar parameters with average uncertainties in effective temperature, surface gravity, and metallicity of 16.5 K, 0.033 and 0.014 dex, respectively. We classify the co-moving pairs of stars into two groups, chemically homogeneous (conatal; |Δ[Fe/H]| ≤ 0.04 dex) and inhomogeneous (non-conatal), and examine the fraction of chemically homogeneous pairs as a function of separation and effective temperature. The four main conclusions from this study are (1) A spatial separation of Δs = 106 au is an approximate boundary between homogeneous and inhomogeneous pairs of stars, and we restrict our conclusions to only consider the 91 pairs with Δs ≤ 106 au; (2) There is no trend between velocity separation and the fraction of chemically homogeneous pairs in the range Δv ≤ 4 km s-1; (3) We confirm that the fraction of chemically inhomogeneous pairs increases with increasing Teff and the trend matches a toy model of that expected from planet ingestion; (4) Atomic diffusion is not the main cause of the chemical inhomogeneity. A major outcome from this study is a sample of 56 bright co-moving pairs of stars with chemical abundance differences ≤ 0.02 dex (5 per cent) which is a level of chemical homogeneity comparable to that of the Hyades open cluster. These important objects can be used, in conjunction with star clusters and the Gaia 'benchmark' stars, to calibrate stellar abundances from large-scale spectroscopic surveys.

Original language	English
Pages (from-to)	2181-2195
Number of pages	15
Journal	Monthly Notices of the Royal Astronomical Society
Volume	526
Issue number	2
DOIs	https://doi.org/10.1093/mnras/stad2679
Publication status	Published - Dec 2023

Keywords

binaries: visual
stars: Abundances
stars: Atmospheres
stars: fundamental parameters

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10.1093/mnras/stad2679Licence: Unspecified

Cite this

@article{473c6dc1fe9f4ae7b87d3a2eed8a1796,

title = "C3PO: Towards a complete census of co-moving pairs of stars-I. High precision stellar parameters for 250 stars",

abstract = "We conduct a line-by-line differential analysis of a sample of 125 co-moving pairs of stars (dwarfs and subgiants near solar metallicity). We obtain high-precision stellar parameters with average uncertainties in effective temperature, surface gravity, and metallicity of 16.5 K, 0.033 and 0.014 dex, respectively. We classify the co-moving pairs of stars into two groups, chemically homogeneous (conatal; |Δ[Fe/H]| ≤ 0.04 dex) and inhomogeneous (non-conatal), and examine the fraction of chemically homogeneous pairs as a function of separation and effective temperature. The four main conclusions from this study are (1) A spatial separation of Δs = 106 au is an approximate boundary between homogeneous and inhomogeneous pairs of stars, and we restrict our conclusions to only consider the 91 pairs with Δs ≤ 106 au; (2) There is no trend between velocity separation and the fraction of chemically homogeneous pairs in the range Δv ≤ 4 km s-1; (3) We confirm that the fraction of chemically inhomogeneous pairs increases with increasing Teff and the trend matches a toy model of that expected from planet ingestion; (4) Atomic diffusion is not the main cause of the chemical inhomogeneity. A major outcome from this study is a sample of 56 bright co-moving pairs of stars with chemical abundance differences ≤ 0.02 dex (5 per cent) which is a level of chemical homogeneity comparable to that of the Hyades open cluster. These important objects can be used, in conjunction with star clusters and the Gaia 'benchmark' stars, to calibrate stellar abundances from large-scale spectroscopic surveys.",

keywords = "binaries: visual, stars: Abundances, stars: Atmospheres, stars: fundamental parameters",

author = "David Yong and Fan Liu and Ting, {Yuan Sen} and Meridith Joyce and Bertram Bitsch and Fei Dai and Aaron Dotter and Karakas, {Amanda I.} and Murphy, {Michael T.}",

note = "Funding Information: This paper includes data gathered with the 6.5-m Magellan Telescopes located at Las Campanas Observatory, Chile. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. Based on observations collected at the European Southern Observatory under ESO programme 108.22EC.001. Funding Information: Parts of this research were supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013. YST acknowledges financial support from the Australian Research Council through DECRA Fellowship DE220101520. MJ gratefully acknowledges funding of MATISSE: Measuring Ages Through Isochrones, Seismology, and Stellar Evolution, awarded through the European Commission{\textquoteright}s Widening Fellowship. This project has received funding from the European Union{\textquoteright}s Horizon 2020 research and innovation programme. BB thanks the European Research Council (ERC Starting Grant 757448-PAMDORA) for their financial support. MTM acknowledges the support of the Australian Research Council through Future Fellowship grant FT180100194. Funding Information: This work has made use of data from the European Space Agency (ESA) mission Gaia ( https://www.cosmos.esa.int/gaia ), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium ). Funding for the DPAC has been provided by national institutions, in particular, the institutions participating in the Gaia Multilateral Agreement. Publisher Copyright: {\textcopyright} 2023 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.",

year = "2023",

month = dec,

doi = "10.1093/mnras/stad2679",

language = "English",

volume = "526",

pages = "2181--2195",

journal = "Monthly Notices of the Royal Astronomical Society",

issn = "0035-8711",

publisher = "Oxford University Press",

number = "2",

}

TY - JOUR

T1 - C3PO

T2 - Towards a complete census of co-moving pairs of stars-I. High precision stellar parameters for 250 stars

AU - Yong, David

AU - Liu, Fan

AU - Ting, Yuan Sen

AU - Joyce, Meridith

AU - Bitsch, Bertram

AU - Dai, Fei

AU - Dotter, Aaron

AU - Karakas, Amanda I.

AU - Murphy, Michael T.

N1 - Funding Information: This paper includes data gathered with the 6.5-m Magellan Telescopes located at Las Campanas Observatory, Chile. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. Based on observations collected at the European Southern Observatory under ESO programme 108.22EC.001. Funding Information: Parts of this research were supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013. YST acknowledges financial support from the Australian Research Council through DECRA Fellowship DE220101520. MJ gratefully acknowledges funding of MATISSE: Measuring Ages Through Isochrones, Seismology, and Stellar Evolution, awarded through the European Commission’s Widening Fellowship. This project has received funding from the European Union’s Horizon 2020 research and innovation programme. BB thanks the European Research Council (ERC Starting Grant 757448-PAMDORA) for their financial support. MTM acknowledges the support of the Australian Research Council through Future Fellowship grant FT180100194. Funding Information: This work has made use of data from the European Space Agency (ESA) mission Gaia ( https://www.cosmos.esa.int/gaia ), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium ). Funding for the DPAC has been provided by national institutions, in particular, the institutions participating in the Gaia Multilateral Agreement. Publisher Copyright: © 2023 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.

PY - 2023/12

Y1 - 2023/12

N2 - We conduct a line-by-line differential analysis of a sample of 125 co-moving pairs of stars (dwarfs and subgiants near solar metallicity). We obtain high-precision stellar parameters with average uncertainties in effective temperature, surface gravity, and metallicity of 16.5 K, 0.033 and 0.014 dex, respectively. We classify the co-moving pairs of stars into two groups, chemically homogeneous (conatal; |Δ[Fe/H]| ≤ 0.04 dex) and inhomogeneous (non-conatal), and examine the fraction of chemically homogeneous pairs as a function of separation and effective temperature. The four main conclusions from this study are (1) A spatial separation of Δs = 106 au is an approximate boundary between homogeneous and inhomogeneous pairs of stars, and we restrict our conclusions to only consider the 91 pairs with Δs ≤ 106 au; (2) There is no trend between velocity separation and the fraction of chemically homogeneous pairs in the range Δv ≤ 4 km s-1; (3) We confirm that the fraction of chemically inhomogeneous pairs increases with increasing Teff and the trend matches a toy model of that expected from planet ingestion; (4) Atomic diffusion is not the main cause of the chemical inhomogeneity. A major outcome from this study is a sample of 56 bright co-moving pairs of stars with chemical abundance differences ≤ 0.02 dex (5 per cent) which is a level of chemical homogeneity comparable to that of the Hyades open cluster. These important objects can be used, in conjunction with star clusters and the Gaia 'benchmark' stars, to calibrate stellar abundances from large-scale spectroscopic surveys.

AB - We conduct a line-by-line differential analysis of a sample of 125 co-moving pairs of stars (dwarfs and subgiants near solar metallicity). We obtain high-precision stellar parameters with average uncertainties in effective temperature, surface gravity, and metallicity of 16.5 K, 0.033 and 0.014 dex, respectively. We classify the co-moving pairs of stars into two groups, chemically homogeneous (conatal; |Δ[Fe/H]| ≤ 0.04 dex) and inhomogeneous (non-conatal), and examine the fraction of chemically homogeneous pairs as a function of separation and effective temperature. The four main conclusions from this study are (1) A spatial separation of Δs = 106 au is an approximate boundary between homogeneous and inhomogeneous pairs of stars, and we restrict our conclusions to only consider the 91 pairs with Δs ≤ 106 au; (2) There is no trend between velocity separation and the fraction of chemically homogeneous pairs in the range Δv ≤ 4 km s-1; (3) We confirm that the fraction of chemically inhomogeneous pairs increases with increasing Teff and the trend matches a toy model of that expected from planet ingestion; (4) Atomic diffusion is not the main cause of the chemical inhomogeneity. A major outcome from this study is a sample of 56 bright co-moving pairs of stars with chemical abundance differences ≤ 0.02 dex (5 per cent) which is a level of chemical homogeneity comparable to that of the Hyades open cluster. These important objects can be used, in conjunction with star clusters and the Gaia 'benchmark' stars, to calibrate stellar abundances from large-scale spectroscopic surveys.

KW - binaries: visual

KW - stars: Abundances

KW - stars: Atmospheres

KW - stars: fundamental parameters

UR - http://www.scopus.com/inward/record.url?scp=85174688388&partnerID=8YFLogxK

U2 - 10.1093/mnras/stad2679

DO - 10.1093/mnras/stad2679

M3 - Article

AN - SCOPUS:85174688388

SN - 0035-8711

VL - 526

SP - 2181

EP - 2195

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

IS - 2

ER -

C3PO: Towards a complete census of co-moving pairs of stars-I. High precision stellar parameters for 250 stars

Abstract

Keywords

Access to Document

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ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions

Cite this

C3PO: Towards a complete census of co-moving pairs of stars-I. High precision stellar parameters for 250 stars

Abstract

Keywords

Access to Document

Other files and links

Projects

ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions

Cite this