The DOI matches its Crossref record; 121 of the 123 references it cites were found in a registry or an index.
The Milky Way has no in-situ halo other than the heated thick disc: Composition of the stellar halo and age-dating the last significant merger with Gaia DR2 and APOGEE
Open accessAbstract
Previous studies based on the analysis of Gaia DR2 data have revealed that accreted stars, possibly originating from a single progenitor satellite, are a significant component of the halo of our Galaxy, potentially constituting most of the halo stars at [Fe/H] < −1 within a few kpc from the Sun and beyond. In this paper, we couple astrometric data from Gaia DR2 with elemental abundances from APOGEE DR14 to characterise the kinematics and chemistry of in-situ and accreted populations up to [Fe/H] ∼ −2. Accreted stars appear to significantly impact the galactic chemo–kinematic relations, not only at [Fe/H] < −1, but also at metallicities typical of the thick and metal-poor thin discs. They constitute about 60% of all stars at [Fe/H] < −1, the remaining 40% being made of (metal-weak) thick-disc stars. We find that the stellar kinematic fossil record shows the imprint left by this accretion event, which heated the old galactic disc. We are able to age-date this kinematic imprint, showing that the accretion occurred between nine and 11 Gyr ago, and that it led to the last significant heating of the galactic disc. An important fraction of stars with abundances typical of the (metal-rich) thick disc, and heated by this interaction, is now found in the galactic halo. Indeed, about half of the kinematically defined halo at few kpc from the Sun is composed of metal-rich thick-disc stars. Moreover, we suggest that this metal-rich thick-disc component dominates the stellar halo of the inner Galaxy. The new picture that emerges from this study is one where the standard, non-rotating in-situ halo population, the collapsed halo, seems to be more elusive than ever.
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“However, the second sequence is populated by stars that, kinematically, are clearly part of the tail of the thick disk seen in Figure 5b (Di Matteo et al. 2019, Haywood et al. 2018).”
From Streams, Substructures, and the Early History of the Milky Way (2020) · cites this paper as Di Matteo et al. 2019
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“These (proto-)thick disk stars were likely dynamically heated during the merger with Gaia-Enceladus (Helmi et al. 2018, Di Matteo et al. 2019).”
From Streams, Substructures, and the Early History of the Milky Way (2020) · cites this paper as Di Matteo et al. 2019
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Cites
Gaia Data Release 2: Summary of the contents and survey properties
Gaia Collaboration, Brown, A. G. A., Vallenari, A., Prusti, T., de Bruijne, J. H. J., Babusiaux, C., Bailer-Jones, C. A. L., Biermann, M., Evans, D. W., Eyer, L., et al. (2018) · Astronomy & Astrophysics · doi:10.1051/0004-6361/201833051 · Cited by 8,442
Self-citationPrusti, T., de Bruijne, J. H. J., Brown, A. G. A., Vallenari, A., Babusiaux, C., Bailer‐Jones, C. A. L., Bastian, U., Biermann, M., Evans, D. W., Eyer, L., et al. (2016) · Astronomy and Astrophysics · doi:10.1051/0004-6361/201629272 · Cited by 7,350
Self-citationGalaxy formation through hierarchical clustering
White, S. D. M., & Frenk, C. S. (1991) · The Astrophysical Journal · doi:10.1086/170483 · Cited by 2,361
Gaia Data Release 2: The astrometric solution
Lindegren, L., Hernández, J., Bombrun, A., Klioner, S., Bastian, U., Ramos-Lerate, M., de Torres, A., Steidelmüller, H., Stephenson, C., Hobbs, D., et al. (2018) · Astronomy & Astrophysics · doi:10.1051/0004-6361/201832727 · Cited by 1,983
Local kinematics and the local standard of rest
Schönrich, R. A., Binney, J. J., & Dehnen, W. (2010) · Monthly Notices of the Royal Astronomical Society · doi:10.1111/j.1365-2966.2010.16253.x · Cited by 1,934
The Apache Point Observatory Galactic Evolution Experiment (APOGEE)
Majewski, S. R., Schiavon, R. P., Frinchaboy, P. M., Prieto, C. A., Barkhouser, R., Bizyaev, D., Blank, B., Brunner, S., Burton, A., Carrera, R., et al. (2017) · The Astronomical Journal · doi:10.3847/1538-3881/aa784d · Cited by 1,831
Evidence from the motions of old stars that the Galaxy collapsed.
Eggen, O. J., Donald Lynden-bell, A., & Sandage, A. (1962) · The Astrophysical Journal · doi:10.1086/147433 · Cited by 1,665
Compositions of halo clusters and the formation of the galactic halo
Searle, L., & Zinn, R. (1978) · The Astrophysical Journal · doi:10.1086/156499 · Cited by 1,524
Reid, M. J., Menten, K. M., Brunthaler, A., Zheng, X. W., Dame, T. M., Xu, Y., Wu, Y., Zhang, B., Sanna, A., Sato, M., et al. (2014) · The Astrophysical Journal · doi:10.1088/0004-637x/783/2/130 · Cited by 1,379
The merger that led to the formation of the Milky Way’s inner stellar halo and thick disk
Helmi, A., Babusiaux, C., Koppelman, H. H., Massari, D., Veljanoski, J., & Brown, A. G. A. (2018) · Nature · doi:10.1038/s41586-018-0625-x · Cited by 1,235
Research works printed but not linked: 6
- Bullock J. S., & Johnston K. V. 2004, in Satellites and Tidal Streams, eds. Prada F., Martinez Delgado D., & Mahoney T. J., ASP Conf. Ser., 327, 80
- Forbes, 2010, MNRAS, 404, 1203
- Navarro, 2011, MNRAS, 412, 1203
- Norris, 1985, ApJ, 58, 463
- Purcell, 2010, MNRAS, 404, 1711
- Zinn R. 1996, in Formation of the Galactic Halo‥ Inside and Out, eds. Morrison H. L., & Sarajedini A., ASP Conf. Ser., 92, 211
Cited by
Sorted by citations
Evidence from the H3 Survey That the Stellar Halo Is Entirely Comprised of Substructure
Naidu, R. P., Conroy, C., Bonaca, A., Johnson, B. D., 丁, Y.-S. 源. T., Caldwell, N., Zaritsky, D., & Cargile, P. A. (2020) · The Astrophysical Journal · doi:10.3847/1538-4357/abaef4 · Cited by 449
Streams, Substructures, and the Early History of the Milky Way
Helmi, A. (2020) · Annual Review of Astronomy and Astrophysics · doi:10.1146/annurev-astro-032620-021917 · Cited by 407
Belokurov, V. A., Sanders, J. L., Fattahi, A., Smith, M. C., Deason, A. J., Evans, N. W., & Grand, R. J. J. (2020) · Monthly Notices of the Royal Astronomical Society · doi:10.1093/mnras/staa876 · Cited by 296
Uncovering the birth of the Milky Way through accurate stellar ages with Gaia
Gallart, C., Bernard, E. J., Brook, C. B., Ruiz-Lara, T., Cassisi, S., Hill, V., & Monelli, M. (2019) · Nature Astronomy · doi:10.1038/s41550-019-0829-5 · Cited by 262
A time-resolved picture of our Milky Way’s early formation history
Xiang, M., & Rix, H. (2022) · Nature · doi:10.1038/s41586-022-04496-5 · Cited by 274
Metadata
- Authors
- Di Matteo, P., Haywood, M., Lehnert, M. D., Katz, D., Khoperskov, S., Snaith, O. N., Gómez, A., & Robichon, N.
- Affiliations
- Centre National de la Recherche Scientifique (FR)
- Korea Institute for Advanced Study (KR)
- Venue
- Astronomy & Astrophysics
- Publisher
- EDP Sciences
- Published
- 2019-11-21
- Volume
- 632
- Pages
- A4
- ISSN
- 0004-6361 (ISSN-L)
- 1432-0746
- OpenAlex
- W3103964408
- Cited by
- 222
- References
- 123
- Citations by year
- 2026: 13 · 2025: 30 · 2024: 30 · 2023: 34 · 2022: 27 · 2021: 49 · 2020: 35 · 2019: 4
- FWCI
- 15.48
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Astronomy and Astrophysics (publishedVersion, cc-by)
- arXiv (Cornell University) (submittedVersion)
- Springer Link (Chiba Institute of Technology) (submittedVersion, cc-by)
- Funders
- Smithsonian Institution
- U.S. Department of Energy
- Alfred P. Sloan Foundation
- Carnegie Institution of Washington
- University of Utah
- Johns Hopkins University
- Carnegie Mellon University
- Carnegie Institution for Science
- European Space Agency
- Agence Nationale de la Recherche (ANR-15-CE31-0007)
- Russian Science Foundation (19–72–20089)
- Instituto de Astrofísica de Canarias
- Office of Science
- Smithsonian Astrophysical Observatory
- Topics
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Stellar, planetary, and galactic studies
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Galaxies: Formation, Evolution, Phenomena
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Astrophysics and Star Formation Studies
- Keywords
- Milky Way stellar halo, thick disk, stellar kinematics, satellite accretion, disk heating, Gaia DR2
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