J/ApJ/900/146ivo://CDS.VizieR/J/ApJ/900/146doi:10.26093/cds/vizier.19000146CDSChun S.-H.Lee J.-J.Lim D.2022-08-25T11:25:14Z2022-02-02T13:48:44ZCDS support team

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

cds-question@unistra.frglobular-star-clusterschemical-abundanceseffective-temperatureinfrared-sourcesWe search for extratidal stars around two metal-poor Galactic globular clusters, M53 and NGC 5053, using the near-infrared APOGEE spectra. Applying the t-distributed stochastic neighbor embedding (t-SNE) algorithm on the chemical abundances and radial velocities results in identification of two isolated stellar groups composed of cluster member stars in the t-SNE projection plane. With additional selection criteria of radial velocity, location in the color-magnitude diagram, and abundances from a manual chemical analysis, we find a total of 73 cluster member candidates; seven extratidal stars are found beyond the tidal radii of the two clusters. The extratidal stars around the clusters tend to be located along the leading direction of the cluster proper motion, and the individual proper motion of these stars also seems to be compatible to those of clusters. Interestingly, we find that one extratidal star of NGC 5053 is located on the southern outskirts of M53, which is part of common stellar envelope by the tidal interaction between two clusters. We discuss the nature of this star in the context of the tidal interaction between two clusters. We find apparent Mg-Al anticorrelations with a clear gap and spread (~0.9dex) in Al abundances for both clusters, and a light Si abundance spread (~0.3dex) for NGC 5053. Since all extratidal stars have Mg-enhanced and Al-depleted features, they could be first-generation stars of two globular clusters. Our results support that M53 and NGC5053 originated in dwarf galaxies and are surrounded by extended stellar substructures of more numerous populations of clusters.2020ApJ...900..146Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/900/146CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/195 : Globular Clusters in the Milky Way (Harris, 1996)VII/202 : Globular Clusters in the Milky Way (Harris, 1997)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)V/150 : Updated cat. of variable stars in globular clusters (Clement+ 2017)I/345 : Gaia DR2 (Gaia Collaboration, 2018)III/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)J/AJ/112/1489 : Spectroscopic survey for binaries in NGC 5053 (Yan+ 1996)J/A+A/320/776 : Tidal radii of 7 globular clusters (Lehmann+ 1997)J/A+A/358/547 : M53 variable stars V light curves (Kopacki, 2000)J/A+A/505/139 : Abundances of red giants in 17 GCs (Carretta+, 2009)J/A+A/497/497 : Physical param. from JHK flux (Gonzalez-Hernandez+, 2009)J/MNRAS/402/226 : NGC 5053 variables VrI light curves (Arellano Ferro+, 2010)J/ApJ/757/164 : Oxygen abundances of dwarf stars (Ramirez+, 2012)J/A+A/557/A128 : Stellar [Fe/H] and [Na/H] in NGC6752 (Carretta, 2013)J/ApJ/804/109 : Equivalent widths of RGB stars in NGC 5053 (Boberg+, 2015)J/AJ/149/153 : Abundances of red giants in 10 GCs (Meszaros+, 2015)J/ApJ/808/16 : Cannon: a new approach to determine abundances (Ness+, 2015)J/ApJ/824/5 : Chemical abundances in NGC 5024 (M53) (Boberg+, 2016)J/AJ/151/144 : ASPCAP weights for APOGEE chemical elements (Garcia+, 2016)J/MNRAS/465/501 : APOGEE N-rich stars in inner Galaxy (Schiavon+, 2017)J/ApJS/228/24 : GALAH semi-automated classification scheme (Traven+, 2017)J/ApJ/865/44 : Abundances of evolved stars from IGRINS. I. (Afsar+, 2018)J/AJ/156/126 : Stellar abundances from BACCHUS analysis (Jonsson+, 2018)J/MNRAS/482/5138 : Galactic GC mean proper motions & vel. (Baumgardt+, 2019)J/A+A/622/A191 : 885 globular cluster giants abundances (Masseron+, 2019)J/MNRAS/484/2832 : Proper motions of MW globular clusters (Vasiliev, 2019)J/A+A/637/A98 : Globular cluster escapees in the Gal. halo (Hanke+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/900/146https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/900/146http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/900/146https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/900/146https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/900/146http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/900/146GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/900/146/table3 (Stellar parameters, metallicity, and abundances of M53 and NGC 5053)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/900/146/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/900/146/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/900/146/table3?GETtext/xml+votable180.050000true205.951463119.51902610.0055555555555555566/8846 8870 26606 27922 27973 27975 27981 27984 27986 27992https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/900/146?format=asciiInfrareddefaultJ/ApJ/900/146/table3Stellar parameters, metallicity, and abundances of M53 and NGC 5053recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint2MASS2MASS identifier (HHMMSSss+DDMMSSs)meta.id;meta.maincharTeff[4120/5120] Effective temperatureKphys.temperature.effectiveintlogg[0.5/1.94] log, surface gravitylog(cm.s**-2)phys.gravityfloatvt[1.66/2.09] microturbulent velocitykm/sphys.velocfloatFeH[-2.33/-1.8] Metallicityphys.abund.Fefloate_FeH[0.006/0.14] Uncertainty in FeHstat.errorfloatMgFe[0.005/0.66]? Mg/Fe relative abundancephys.abundfloatnullablee_MgFe[0.014/0.14]? Uncertainty in MgFestat.errorfloatnullableAlFe[-0.42/1.3]? Al/Fe relative abundancephys.abundfloatnullablee_AlFe[0.01/0.2]? Uncertainty in AlFestat.errorfloatnullableSiFe[0.2/0.65]? Si/Fe relative abundancephys.abundfloatnullablee_SiFe[0.012/0.18]? Uncertainty in SiFestat.errorfloatnullableClusterCluster surveyed ("M53"=44 occurrences or "NGC 5053"=21 occurrences)meta.id.parentcharAPDisplay data from APOGEE-2 DR16 (III/284)meta.ref.urlintnullableN15Display data from Ness+, 2015, J/ApJ/808/16meta.ref.urlintnullableSimbadSimbad column added by the CDSmeta.ref.urlchar_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