J/AJ/162/109ivo://CDS.VizieR/J/AJ/162/109doi:10.26093/cds/vizier.51620109CDSSchuler S.C.Andrews J.J.Clanzy V.R.Mourabit M.Chaname J.,Agueros M.A.2022-09-30T22:13:29Z2022-01-31T07:53:51ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frvariable-starsvisible-astronomyspectroscopyWhile most moving groups are young and nearby, a small number have been identified in the Galactic halo. Understanding the origin and evolution of these groups is an important piece of reconstructing the formation history of the halo. Here we report on our analysis of three putative halo moving groups: G03-37, G18-39, and G21-22. Based on Gaia EDR3 data, the stars associated with each group show some scatter in velocity (e.g., Toomre diagram) and integrals of motion (energy, angular momentum) spaces, counter to expectations of moving-group stars. We choose the best candidate of the three groups, G21-22, for follow-up chemical analysis based on high-resolution spectroscopy of six presumptive members. Using a new Python code that uses a Bayesian method to self-consistently propagate uncertainties from stellar atmosphere solutions in calculating individual abundances and spectral synthesis, we derive the abundances of {alpha}-(Mg, Si, Ca, Ti), Fe-peak (Cr, Sc, Mn, Fe, Ni), odd-Z (Na, Al, V), and neutron-capture (Ba, Eu) elements for each star. We find that the G21-22 stars are not chemically homogeneous. Based on the kinematic analysis for all three groups and the chemical analysis for G21-22, we conclude the three are not genuine moving groups. The case for G21-22 demonstrates the benefit of combining kinematic and chemical information in identifying conatal populations when either alone may be insufficient. Comparing the integrals of motion and velocities of the six G21-22 stars with those of known structures in the halo, we tentatively associate them with the Gaia-Enceladus accretion event.2021AJ....162..109Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/162/109CatalogResearchIsServedByTAP VizieR generic servicerelated-toI/316 : Lowell GR* red stars (Giclas+ 1972-1978)I/345 : Gaia DR2 (Gaia Collaboration, 2018)J/ApJ/757/164 : Oxygen abundances of dwarf stars (Ramirez+, 2012)J/ApJ/771/67 : Detailed abundances 97 metal-poor stars. II. (Ishigaki+, 2013)J/AJ/147/136 : Stars very low metal abundance.VI. Abundances (Roederer+, 2014)J/ApJ/808/103 : Kapteyn moving group star abundances (Navarrete+, 2015)J/ApJ/815/5 : Detailed abundances KOI stars with planets. I. (Schuler+, 2015)J/A+A/616/A10 : 46 open clusters GaiaDR2 HR diagrams (Gaia Collaboration, 2018)J/AJ/156/18 : APOGEE DR14,Binary comps of evolved stars (Price-Whelan+, 2018)J/ApJ/852/49 : Properties of metal-poor stars in APOGEE DR13 (Hayes+, 2018)J/ApJ/855/83 : Abundances very metal-poor stars in Sagittarius (Hansen+, 2018)J/ApJS/237/8 : Line lists for X^1^{Sigma}^+^ AlF and AlCl (Yousefi+, 2018)J/ApJ/874/148 : Metal-poor star RAVEJ093730.5-062655 abundances (Sakari+, 2019)J/ApJ/891/39 : LAMOST DR3 very metal-poor stars of Galactic halo (Yuan+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/162/109https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/162/109http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/162/109https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/162/109https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/162/109http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/162/109GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/162/109/table2Linelist and equivalent widths for putative members of G21-22recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSpeciesSpecies identifiermeta.id;meta.maincharWave[4798/6751] Rest wavelength; Angstroms0.1nmem.wlfloatExPot[0/5.7] Excitation potentialeVphys.atmol.excitationfloatlogg[-5.5/0.57] log oscillator strengthphys.gravityfloatEW1[3.5/102]? G02-38 equivalent width; milli-Angstroms1e-13mspect.line.widthfloatnullableEW2[3.2/170]? G82-42 equivalent width; milli-Angstroms1e-13mspect.line.widthfloatnullableEW3[5.3/98.9]? G108-48 equivalent width; milli-Angstroms1e-13mspect.line.widthfloatnullableEW4[3.5/94.5]? G119-64 equivalent width; milli-Angstroms1e-13mspect.line.widthfloatnullableEW5[2.3/122]? G161-73 equivalent width; milli-Angstroms1e-13mspect.line.widthfloatnullableEW6[3.7/127]? HIP 36878 equivalent width; milli-Angstroms1e-13mspect.line.eqWidthfloatnullable