J/MNRAS/377/300ivo://CDS.VizieR/J/MNRAS/377/300doi:10.26093/cds/vizier.73770300CDSPiatti A.E.Sarajedini A.Geisler D.Clark D.Seguel J.2024-07-04T20:18:16Z2008-05-01T13:50:44ZCDS support team

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

cds-question@unistra.frmagellanic-cloudsstellar-associationsvisible-astronomybroad-band-photometryWe present CCD photometry in the Washington C and T1 filters for six star clusters (B 34, NGC 256, NGC 265, NGC 294, IC 1611 and NGC 376) in the Small Magellanic Cloud (SMC) and their surrounding fields. The resultant colour-magnitude diagrams (CMDs) extend from T1~14 to as faint as T1~22 revealing the main-sequence turnoffs of the clusters. Adopting a metallicity of Z=0.004, we compare our cluster photometry with theoretical isochrones in the Washington system in order to derive ages. To facilitate age determination of the surrounding fields, we use the magnitude difference between the helium-burning red clump stars and the main-sequence turnoff. Finally, we estimate mean metallicities for the field stars by comparing the location of the field red giant branch with standard giant branches for Galactic globular clusters of known abundance, corrected for age effects. Combining these results with our previous work, we find a clear trend of younger clusters being located closer to the centre of the SMC. In addition, there is a tendency for the mean metallicity and its dispersion to be greater inside 4{deg} of the SMC's centre as compared to outside this radius. As far as the properties of the field stars are concerned, we find little correlation between the ages of the clusters and those of the field stars against which they are projected. Clearly, more work needs to be done to clarify these trends.2007MNRAS.377..300Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/377/300CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/377/300https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/377/300http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/377/300https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/377/300https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/377/300http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/377/300GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/MNRAS/377/300/table2CCD CT1 data of stars in the field of B 34recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqSequential number of the star (1)meta.recordintXposX position (2)pixpos.cartesian.x;instr.detdoubleYposY position (2)pixpos.cartesian.y;instr.detdoubleT1magWashington T1 magnitudemagphot.mag;em.opt.Rfloate_T1magrms uncertainty on T1 (3)magstat.error;phot.magfloatC-T1? Washington C-T1 colour indexmagphot.color;em.opt.U;em.opt.Rfloatnullablee_C-T1? rms uncertainty on C-T1 (3)magstat.errorfloatnullableo_T1magNumber of observationsmeta.numberintJ/MNRAS/377/300/table3CCD CT1 data of stars in the field of NGC 256recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqSequential number of the star (1)meta.recordintXposX position (2)pixpos.cartesian.x;instr.detdoubleYposY position (2)pixpos.cartesian.y;instr.detdoubleT1magWashington T1 magnitudemagphot.mag;em.opt.Rfloate_T1magrms uncertainty on T1 (3)magstat.error;phot.magfloatC-T1? Washington C-T1 colour indexmagphot.color;em.opt.U;em.opt.Rfloatnullablee_C-T1? rms uncertainty on C-T1 (3)magstat.errorfloatnullableo_T1magNumber of observationsmeta.numberintJ/MNRAS/377/300/table4CCD CT1 data of stars in the field of NGC 265recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqSequential number of the star (1)meta.recordintXposX position (2)pixpos.cartesian.x;instr.detdoubleYposY position (2)pixpos.cartesian.y;instr.detdoubleT1magWashington T1 magnitudemagphot.mag;em.opt.Rfloate_T1magrms uncertainty on T1 (3)magstat.error;phot.magfloatC-T1? Washington C-T1 colour indexmagphot.color;em.opt.U;em.opt.Rfloatnullablee_C-T1? rms uncertainty on C-T1 (3)magstat.errorfloatnullableo_T1magNumber of observationsmeta.numberintJ/MNRAS/377/300/table5CCD CT1 data of stars in the field of NGC 294recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqSequential number of the star (1)meta.recordintXposX position (2)pixpos.cartesian.x;instr.detdoubleYposY position (2)pixpos.cartesian.y;instr.detdoubleT1magWashington T1 magnitudemagphot.mag;em.opt.Rfloate_T1magrms uncertainty on T1 (3)magstat.error;phot.magfloatC-T1? Washington C-T1 colour indexmagphot.color;em.opt.U;em.opt.Rfloatnullablee_C-T1? rms uncertainty on C-T1 (3)magstat.errorfloatnullableo_T1magNumber of observationsmeta.numberintJ/MNRAS/377/300/table6CCD CT1 data of stars in the field of IC 1611recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqSequential number of the star (1)meta.recordintXposX position (2)pixpos.cartesian.x;instr.detdoubleYposY position (2)pixpos.cartesian.y;instr.detdoubleT1magWashington T1 magnitudemagphot.mag;em.opt.Rfloate_T1magrms uncertainty on T1 (3)magstat.error;phot.magfloatC-T1? Washington C-T1 colour indexmagphot.color;em.opt.U;em.opt.Rfloatnullablee_C-T1? rms uncertainty on C-T1 (3)magstat.errorfloatnullableo_T1magNumber of observationsmeta.numberintJ/MNRAS/377/300/table7CCD CT1 data of stars in the field of NGC 376recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqSequential number of the star (1)meta.recordintXposX position (2)pixpos.cartesian.x;instr.detdoubleYposY position (2)pixpos.cartesian.y;instr.detdoubleT1magWashington T1 magnitudemagphot.mag;em.opt.Rfloate_T1magrms uncertainty on T1 (3)magstat.error;phot.magfloatC-T1? Washington C-T1 colour indexmagphot.color;em.opt.U;em.opt.Rfloatnullablee_C-T1? rms uncertainty on C-T1 (3)magstat.errorfloatnullableo_T1magNumber of observationsmeta.numberint