J/ApJ/743/149ivo://CDS.VizieR/J/ApJ/743/149doi:10.26093/cds/vizier.17430149CDSYoon S.-J.Sohn S.T.Lee S.-Y.Kim H.-S.Cho J.Chung C.,Blakeslee J.P.2013-07-16T13:57:09Z2013-06-27T08:37:08ZCDS support team

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

cds-question@unistra.frglobular-star-clustershst-photometrygalaxiesWe here propose a new photometric technique to probe the possible nonlinear nature of globular clusters (GCs) color-metallicity relations (CMRs). In essence, a color distribution of GCs is a "projected" distribution of their metallicities. Since the form of CMRs hinges on which color is used, the shape of color distributions varies depending significantly on the colors. Among other optical colors, the u-band related colors (e.g., u-g and u-z) are theoretically predicted to exhibit significantly less inflected CMRs than other preferred CMRs (e.g., for g-z). As a case study, we performed the Hubble Space Telescope (HST)/WFPC2 archival u-band photometry for the M87 (NGC 4486) GC system with confirmed color bimodality. We show that the u-band color distributions are significantly different from that of g-z and consistent with our model predictions. With more u-band measurements, this method will support or rule out the nonlinear CMR scenario for the origin of GC color bimodality with high confidence.2011ApJ...743..149Yhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/743/149CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/hst : HST Archived Exposures Catalog (STScI, 2007)J/ApJS/197/33 : The M87 globular cluster system (Strader+, 2011)J/ApJ/703/42 : HST photometry of M87 globular clusters (Peng+, 2009)J/ApJS/180/54 : GC candidates in ACS Virgo survey (Jordan+, 2009)J/MNRAS/382/1947 : CT1 photometry in NGC 1399 and NGC 4486 (Forte+, 2007)J/AJ/131/866 : Hot populations in M87 globular clusters (Sohn+, 2006)J/ApJ/613/279 : ACS Virgo Cluster Survey. III. M87 (Jordan+, 2004)J/ApJ/559/812 : Globular cluster system in M87 (Hanes+, 2001)J/ApJ/513/733 : Globular cluster system in M87 (Kundu+, 1999)J/AJ/115/1801 : VRI photometry of M87 globular clusters (Harris+ 1998)J/AJ/106/493 : Globular clusters in M87 (Lee+, 1993)J/ApJS/73/671 : M87 globular clusters BVI photometry (Couture+, 1990)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/743/149https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/743/149http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/743/149https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/743/149https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/743/149http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/743/149GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/743/149/table5 (The u-, g-, and z-band magnitudes and their observational errors for the M87 GCs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/743/149/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/743/149/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/743/149/table5?GETtext/xml+votable180.050000true187.705642712.39097020.0055555555555555566/277652.1350832807657816e-19 6.367785378457404e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/743/149?format=asciiOpticaldefaultJ/ApJ/743/149/table5The u-, g-, and z-band magnitudes and their observational errors for the M87 GCsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqGlobular cluster running sequence numbermeta.id;meta.mainintRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainumagThe u (HST/WFPC2 F336W) band AB magnitudemagphot.mag;em.opt.Ufloate_umagError in umagmagstat.error;phot.mag;em.opt.UfloatgmagThe g (HST/ACS F475W) band AB magnitude (1)magphot.mag;em.opt.Bfloate_gmagError in gmag (1)magstat.error;phot.mag;em.opt.BfloatzmagThe z (HST/ACS) F850LP) band AB magnitude (1)magphot.mag;em.opt.Ifloate_zmagError in zmag (1)magstat.error;phot.mag;em.opt.IfloatJ09Cross-match with Jordan et al. 2009, Cat. J/ApJS/180/54, within 0.2"meta.ref.urlintnullable