Dynamically tagged groups of metal-poor stars. I.

DOI

Orbital characteristics based on Gaia Early Data Release 3 astrometric parameters are analyzed for ~4000 metal-poor stars ([Fe/H]<=-0.8) compiled from the Best and Brightest survey. Selected as metal-poor candidates based on broadband near- and far-IR photometry, 43% of these stars had medium-resolution (1200<=R<=2000) validation spectra obtained over a 7yr campaign from 2014 to 2020 with a variety of telescopes. The remaining stars were chosen based on photometric metallicity determinations from the Huang et al. recalibration of the Sky Mapper Southern Survey. Dynamical clusters of these stars are obtained from the orbital energy and cylindrical actions using the HDBSCAN unsupervised learning algorithm. We identify 52 dynamically tagged groups (DTGs) with between five and 21 members; 18 DTGs have at least 10 member stars. Milky Way (MW) substructures such as Gaia-Sausage-Enceladus, the Metal-Weak Thick-Disk, Thamnos, the Splashed Disk, and the Helmi Stream are identified. Associations with MW globular clusters are determined for eight DTGs; no recognized MW dwarf galaxies were associated with any of our DTGs. Previously identified dynamical groups are also associated with our DTGs, with emphasis placed on their structural determination and possible new identifications. Chemically peculiar stars are identified as members of several DTGs, with six DTGs that are associated with r-process-enhanced stars. We demonstrate that the mean carbon and {alpha}-element abundances of our DTGs are correlated with their mean metallicity in an understandable manner. Similarly, we find that the mean metallicity, carbon, and {alpha}-element abundances are separable into different regions of the mean rotational-velocity space.

Cone search capability for table J/ApJ/926/26/table2 (*Stellar members of identified DTGs by HDBSCAN)

Cone search capability for table J/ApJ/926/26/table6 (Initial from the best and brightest survey)

Cone search capability for table J/ApJ/926/26/table7 (The final from the best and brightest survey)

Identifier
DOI http://doi.org/10.26093/cds/vizier.19260026
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/926/26
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/926/26
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/926/26
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/926/26
Provenance
Creator Shank D.; Beers T.C.; Placco V.M.; Limberg G.; Jaques E.; Yuan Z.,Schlaufman K.C.; Casey A.R.; Huang Y.; Lee Y.S.; Hattori K.; Santucci R.M.
Publisher CDS
Publication Year 2022
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Exoplanet Astronomy; Galactic and extragalactic Astronomy; Interdisciplinary Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy