J/A+A/648/A108ivo://CDS.VizieR/J/A+A/648/A108doi:10.26093/cds/vizier.36480108CDSRecio-Blanco A.Fernandez-Alvar E.de Laverny P.Antoja T.Helmi A.,Crida A.2021-12-07T12:45:58Z2021-04-21T07:32:44ZCDS support team

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

cds-question@unistra.frmilky-way-galaxyglobular-star-clusterschemical-abundancesA fundamental element of galaxy formation is the accretion of mass through mergers of satellites or gas. Recent dynamical analyses based on Gaia data have revealed major accretion events in the history of the Milky Way. Nevertheless, our understanding of the primordial Galaxy is hindered because the bona fide identification of the most metal-poor and correspondingly oldest accreted stars remains challenging. Galactic archaeology needs a new accretion diagnostic to understand primordial stellar populations. Contrary to {alpha}-elements, neutron-capture elements present unexplained large abundance spreads for low-metallicity stars, which could result from a mixture of formation sites. We analysed the abundances of yttrium, europium, magnesium, and iron in MilkyWay satellite galaxies, field halo stars, and globular clusters. The chemical information was complemented by orbital parameters based on Gaia data. In particular, we considered the average inclination of the orbits. The [Y/Eu] abundance behaviour with respect to the [Mg/Fe] turnovers for satellite galaxies of various masses reveals that higher-luminosity systems, for which the [Mg/Fe] abundance declines at higher metallicities, present enhanced [Y/Eu] abundances, particularly in the [Fe/H] regime between -2.25dex and -1.25dex. In addition, the analysis has uncovered a chemo-dynamical correlation for both globular clusters and field stars of the Galactic halo, accounting for about half of the [Y/Eu] abundance spread. In particular, [Y/Eu] under-abundances typical of protracted chemical evolutions are preferentially observed in polar-like orbits, pointing to a possible anisotropy in the accretion processes. Our results strongly suggest that the observed [Y/Eu] abundance spread in the Milky Way halo could result from a mixture of systems with different masses. They also highlight that both nature and nurture are relevant to the formation of the Milky Way since its primordial epochs, thereby opening new pathways for chemical diagnostics of the build-up of our Galaxy.2021A&A...648A.108Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/648/A108CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/147/136 : Stars of very low metal abundance. VI. AbundancesJ/MNRAS/484/2832 : Proper motions of Milky Way globular clustershttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/648/A108https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/648/A108http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/648/A108https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/648/A108https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/648/A108http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/648/A108GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/648/A108/table2 (Chemical abundances and orbital parameters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/648/A108/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/648/A108/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/648/A108/table2?GETtext/xml+votable180.050000true15.8094167-70.84877780.0055555555555555566/8235 9436 9666 10336 12405 12451 12943 17245 17380 17420 19091 19347 19385 23096 24775 24827 24843 24942 26534 26589 27237 27981 28973 29765 30296 31377 31398 31417 31723 33273 33321 33330 33470 33508 33635 34242 35768 36193 38465 39157 39642 40716 41522 41721 42076 42841 42990 43125 44427 44653 45881 46053 46399 46540 46676 47125 47971 48394 48501 48937https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/648/A108?format=asciidefaultJ/A+A/648/A108/table2Chemical abundances and orbital parametersSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRefReferences code (1)meta.codecharObjectTarget namemeta.id;meta.mainchar[Fe/H]Iron abundancephys.abund.Fefloat[alpha/Fe]? alpha element abundance with respect to ironphys.abundfloatnullable[Y/Fe]Yttrium abundance with respect to ironphys.abundfloat[Eu/Fe]Europium abundance with respect to ironphys.abundfloatInclOrbital inclinationdegsrc.orbital.inclinationfloat_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main