J/A+A/664/A168ivo://CDS.VizieR/J/A+A/664/A168doi:10.26093/cds/vizier.36640168CDSDe Bortoli B.J.Parisi M.C.Bassino L.P.Geisler D.Dias B.Gimeno G.,Angelo M.S.Mauro F.2023-11-07T10:29:46Z2022-08-25T09:18:05ZCDS support team

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

cds-question@unistra.frmagellanic-cloudsgiant-starsradial-velocityvisible-astronomyline-intensitiesmetallicityWe aim to analyze the chemical evolution of the Main Body of the SMC, adding six additional clusters to previously published samples, based on homogeneously determined and accurate metallicities. We derived radial velocities and CaII Triplet (CaT) metallicity of more than 150 red giants stars in six SMC star clusters and their surrounding fields, with the instrument GMOS on GEMINI-S. The mean cluster radial velocity and metallicity were obtained with mean errors of 2.2km/s and 0.03dex, while the mean field metallicities have a mean error of 0.13dex. We add this information to that available for another 51 clusters and 30 fields with CaT metallicities on the same scale. Using this expanded sample we analize the chemical properties of the SMC Main Body, defined as the inner 3.4 degrees in semimajor axis. We found a high probability that the metallicity distribution of the Main Body clusters is bimodal with a metal-rich and a metal-poor cluster group, having mean metallicities with a dispersion of {mu}=-0.80, {sigma}=0.06 and {mu} = -1.15, {sigma}=0.10dex, respectively. On the other hand,Main Body field stars show a unimodal metallicity distribution peaking at [Fe/H]~-1 and dispersion of 0.3. Neither metal-rich nor metal-poor clusters present a metallicity gradient. However the full Main Body cluster sample and field stars have a negative metallicity gradient consistent with each other, but the one corresponding to clusters has a large error due to the large metallicity dispersion present in the clusters studied in that region. Metal-rich clusters present a clear age-metallicity relation, while metal-poor clusters present no chemical enrichment throughout the life of the galaxy. We present observational evidence that the chemical enrichment is complex in the SMC Main Body. Two cluster groups with potential different origins could be coexisting in the Main Body. More data with precise and homogeneous metallicities and distances are needed and dynamical simulations are required to understand possible different origins for the two possible cluster groups.2022A&A...664A.168Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/664/A168CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/138/517 : CaII spectroscopy of SMC red giants (Parisi+, 2009)J/AJ/139/1168 : CaII spectroscopy of SMC fields stars (Parisi+, 2010)J/AJ/149/154 : CaII spectroscopy of SMC red giants. III. (Parisi+, 2015)J/AJ/152/58 : CaII spectroscopy of SMC red giants. IV. (Parisi+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/664/A168https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/664/A168http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/664/A168https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/664/A168https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/664/A168http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/664/A168GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/664/A168/table1 (Selected SMC cluster sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/664/A168/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/664/A168/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/664/A168/table1?GETtext/xml+votable180.050000true14.45625-73.4230560.005555555555555556Cone search capability for table J/A+A/664/A168/table2 (Measured parameters for the observed RGB stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/664/A168/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/664/A168/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/664/A168/table2?GETtext/xml+votable180.050000true14.4554167-73.379050.0055555555555555566/33287 33293 33295 33304 33313 33328 33330https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/664/A168?format=asciiOpticaldefaultJ/A+A/664/A168/table1Selected SMC cluster samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintClusterCluster namemeta.id.parentcharRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainaProjected distance to the SMC centredegpos.angDistancefloatl_Age[~] Limit flag on Agemeta.code.error;time.agecharAgeAgeGyrtime.agefloate_Age? rms uncertainty on AgeGyrstat.error;time.agefloatnullabler_Age[1/3] Age reference (1)meta.ref;pos.frameintNNumber of members in table2.datmeta.numberintSNameSimbad namemeta.idcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/A+A/664/A168/table2Measured parameters for the observed RGB starsSimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintClusterCluster namemeta.id.parentcharIDCluster member identification numbermeta.id;meta.mainintRAJ2000Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainRVHeliocentric radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloate_RVThe 1{sigma} error in RVkm/sstat.errorfloatg-gHB? Brightness difference between star and cluster's horizontal branchmagphot.mag;arith.difffloatnullableSigmaW? Summed CaII equivalent width (1)0.1nmspect.line.eqWidthfloatnullablee_SigmaW? The 1{sigma} error in SigmaW0.1nmstat.errorfloatnullable[Fe/H]? Metallicityphys.abund.Zfloatnullablee_[Fe/H]? The error in Metallicitystat.error;phys.abund.FefloatnullableC/F[C/F] Cluster (C) or field (F) starmeta.codechar