J/ApJ/700/103ivo://CDS.VizieR/J/ApJ/700/103doi:10.26093/cds/vizier.17000103CDSPark W.-K.Park H.S.Lee M.G.2017-11-29T11:48:24Z2011-08-09T12:02:39ZCDS support team

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

cds-question@unistra.frstellar-associationsgalaxiesastronomical-object-identificationWe present a result of age estimation for star clusters in M33. We obtain color-magnitude diagrams (CMDs) of resolved stars in 242 star clusters from the Hubble Space Telescope/Wide Field Planetary Camera 2 images. We estimate ages of 100 star clusters among these, by fitting the Padova theoretical isochrones to the observational CMDs. Age distribution of the star clusters shows a dominant peak at log(t)~7.8. Majority of star clusters are younger than log(t)=9.0, while 10 star clusters are older than log(t)~9.0. There is only one cluster younger than log(t)=7 in this study, which is in contrast with the results based on the integrated photometry of star clusters in the previous studies. Radial distribution of the cluster ages shows that young- to intermediate-age clusters are found from the center to the outer region, while old clusters are distributed farther from the M33 center. We briefly discuss the implication of the results with regard to the formation of the M33 cluster system.2009ApJ...700..103Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/700/103CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/hst : HST Archived Exposures Catalog (STScI, 2007)J/ApJ/699/839 : Newly identified star clusters in M33. II. (San+, 2009)J/AJ/134/447 : Catalog of star cluster candidates in M33 (Sarajedini+, 2007)J/AJ/134/2168 : BVI photometry of M33 star clusters (Park+, 2007)J/A+A/444/831 : New star clusters in M33 (Bedin+, 2005)J/A+A/366/498 : VI photometry of M33 star clusters (Chandar+, 2001)J/ApJS/122/431 : Star Clusters in M33 (Chandar+, 1999)J/AcA/48/455 : Globular Clusters in M31 and M33 (Mochejska+, 1998)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/700/103https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/700/103http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/700/103https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/700/103https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/700/103http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/700/103GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/700/103/table1 (Ages of M33 star clusters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/700/103/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/700/103/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/700/103/table1?GETtext/xml+votable180.050000true23.298916730.64892780.0055555555555555566/2154 2155https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/700/103?format=asciiOpticaldefaultJ/ApJ/700/103/table1Ages of M33 star clustersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[PL2007]Cluster ID number from Park & Lee 2007, Cat. J/AJ/134/2168meta.id;meta.mainintlog(t)Log of estimated agelog(yr)time.agefloatu_log(t)[:] Uncertainty flag on log(t) (1)meta.code.errorcharE_log(t)Upper error of log(t)log(yr)stat.error;stat.maxfloate_log(t)Lower error of log(t)log(yr)stat.errorfloatZMetallicity Z used during isochrone fittingphys.abund.Z;instr.setupfloatE(B-V)The reddening used during isochrone fittingmagphot.color.excessfloate_E(B-V)Error in E(B-V)magstat.errorfloatRadiusMember star selection radiusarcsecphys.angSizefloatONameCross-identification with previous catalogs (2)meta.id.crosscharXmNumber of cross-matches with other catalogs of clusters in M33intnullableSimbadSimbad column added by the CDSchar_RAPositions from Park & Lee 2007, Cat. J/AJ/134/2168 (right ascension part)degpos.eq.ra;meta.main_DEPositions from Park & Lee 2007, Cat. J/AJ/134/2168 (declination part)degpos.eq.dec;meta.main