J/ApJS/256/29ivo://CDS.VizieR/J/ApJS/256/29doi:10.26093/cds/vizier.22560029CDSKim S.Yoon S.-J.Lee S.-Y.Chung C.Sohn S.T.2022-07-28T07:30:04Z2022-03-02T13:20:48ZCDS support team

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

cds-question@unistra.frglobular-star-clustersvisible-astronomyspectroscopyradial-velocitychemical-abundancestwo-color-diagramsWe obtained spectra of some 140 globular clusters (GCs) associated with the Virgo central cD galaxy M87 with the Subaru/FOCAS MOS mode. The fundamental properties of GCs such as age, metallicity, and {alpha}-element abundance are investigated by using simple stellar population models. It is confirmed that the majority of M87 GCs are as old as, more metal-rich than, and more enhanced in {alpha}-elements than the Milky Way GCs. Our high-quality, homogeneous data set enables us to test the theoretical prediction of inflected color-metallicity relations (CMRs). The nonlinear-CMR hypothesis entails an alternative explanation for the widely observed GC color bimodality, in which even a unimodal metallicity spread yields a bimodal color distribution by virtue of nonlinear metallicity-to-color conversion. The newly derived CMRs of old, high-signal-to-noise-ratio GCs in M87 (the V-I CMR of 83 GCs and the M-T2 CMR of 78 GCs) corroborate the presence of the significant inflection. Furthermore, from a combined catalog with the previous study on M87 GC spectroscopy, we find that a total of 185 old GCs exhibit a broad, unimodal metallicity distribution. The results corroborate the nonlinear-CMR interpretation of the GC color bimodality, shedding further light on theories of galaxy formation.2021ApJS..256...29Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/256/29CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/195 : Globular Clusters in the Milky Way (Harris, 1996)VII/202 : Globular Clusters in the Milky Way (Harris, 1997)J/AJ/105/1762 : Globular clusters around NGC 1399 (Ostrov+ 1993)J/AJ/106/493 : Globular clusters in M87 (Lee+, 1993)J/ApJS/111/377 : H{gamma} & H{delta} absorption features (Worthey+ 1997)J/ApJS/116/1 : Old Stellar Populations. VI. Absorption-Line (Trager+ 1998)J/AJ/115/1801 : VRI photometry of M87 globular clusters (Harris+ 1998)J/ApJ/513/733 : Globular cluster system in M87 (Kundu+, 1999)J/ApJ/559/812 : Globular cluster system in M87 (Hanes+, 2001)J/ApJ/613/279 : ACS Virgo Cluster Survey. III. M87 (Jordan+, 2004)J/ApJ/621/673 : Line indices for 124 early-type galaxies (Thomas+, 2005)J/AJ/131/866 : Hot populations in M87 globular clusters (Sohn+, 2006)J/MNRAS/382/1947 : CT1 photometry in NGC 1399 and NGC 4486 (Forte+, 2007)J/ApJ/674/857 : Radial velocities and CT1 magnitudes in M60 galaxy (Lee+, 2008)J/MNRAS/386/1443 : 2dF study of globular clusters in NGC 5128 (Beasley+, 2008)J/ApJS/180/54 : GC candidates in ACS Virgo survey. (Jordan+, 2009)J/ApJ/703/42 : HST photometry of M87 globular clusters (Peng+, 2009)J/ApJ/708/1335 : Spectroscopy of globulars in NGC 5128 (Woodley+, 2010)J/AJ/140/2101 : NGC 5128 globular clusters photometry (Sinnott+, 2010)J/AJ/141/61 : Star clusters in M31. II. (Caldwell+, 2011)J/ApJ/743/149 : Color-metallicity relations. II. M87 GCs (Yoon+, 2011)J/ApJS/197/33 : The M87 globular cluster system (Strader+, 2011)J/ApJ/746/88 : HST observations of GCs in NGC 1399 (Blakeslee+, 2012)J/ApJ/748/29 : Spectroscopy of M87 globular clusters (Romanowsky+, 2012)J/MNRAS/428/389 : SLUGGS globular clusters in early-type galaxies (Pota+, 2013)J/ApJ/768/137 : HST photometry of M84 globular clusters (Yoon+, 2013)J/MNRAS/446/369 : Colour & spectral index from the SLUGGS survey (Usher+, 2015)J/A+A/574/A21 : Isolated elliptical galaxies and GC (Richtler+, 2015)J/MNRAS/455/820 : M87 globular cluster candidates catalog (Oldham+, 2016)J/MNRAS/458/105 : SLUGGS NGC 3607 and 3608 globular clusters (Kartha+, 2016)J/ApJ/835/212 : Wide-field spec. survey of GCs in Virgo cluster (Ko+, 2017)J/AJ/156/6 : Light element abund. of RGB & AGB stars in M10 (Gerber+, 2018)J/ApJ/900/95 : New M87 GCs metallicities from Keck & MMT sp. (Villaume+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/256/29https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/256/29http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/256/29https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/256/29https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/256/29http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/256/29GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/256/29/m87gcs (Radial velocity and lick index measurements of M87 globular clusters (Tables 2, 3 and 4))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/256/29/m87gcs?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/256/29/m87gcs?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/256/29/m87gcs?GETtext/xml+votable180.050000true187.7215512.45610.0055555555555555566/197193.322582951404819e-19 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/256/29?format=asciiOpticaldefaultJ/ApJS/256/29/m87gcsRadial velocity and lick index measurements of M87 globular clusters (Tables 2, 3 and 4)CN1[-0.42/0.53]? Lick CN1 metal indexmagspect.indexfloatnullablee_HgF? Lick H{gamma}F Balmer index uncertainty (1)0.1nmstat.errorfloatnullablee_Fe4383? Lick Fe4383 metal index uncertainty (1)0.1nmstat.errorfloatnullableCN2[-0.9/0.6]? Lick CN2 metal indexmagspect.indexfloatnullableRAJ2000Right Ascension in decimal hours (J2000)degpos.eq.ra;meta.mainIDIdentifiermeta.id;meta.mainchare_Fe5015Lick Fe5015 metal index uncertainty (1)0.1nmstat.errorfloate_Mg1? Lick Mg1 metal index uncertaintymagstat.errorfloatnullablee_Mg2? Lick Mg2 metal index uncertaintymagstat.errorfloatnullablee_MgbLick Mgb metal index uncertainty (1)0.1nmstat.errorfloate_Fe5270? Lick Fe5270 metal index uncertainty (1)0.1nmstat.errorfloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainVmag[18.64/22.37] Apparent Johnson V band Vega magnitudemagphot.mag;em.opt.VfloatV-I[0.89/1.35] The Johnson (V-I) color indexmagphot.color;em.opt.V;em.opt.IfloatRVel[259.5/2034] Radial velocitykm/sphys.veloc;pos.heliocentricfloatHdA[-11.3/10.9]? Lick H{delta}A Balmer index (1)0.1nmspect.indexdoublenullableHdF[-5.8/5.8]? Lick H{delta}F Balmer index (1)0.1nmspect.indexfloatnullableCa4227[-2/30.6]? Lick Ca4227 metal index (1)0.1nmspect.indexfloatnullableG4300[-5.6/11]? Lick G4300 metal index (1)0.1nmspect.indexfloatnullableHgA[-10.01/5.7]? Lick H{gamma}A Balmer index (1)0.1nmspect.indexdoublenullableHgF[-4.53/4.53]? Lick H{gamma}F Balmer index (1)0.1nmspect.indexfloatnullableFe4383[-16.2/10.15]? Lick Fe4383 metal index (1)0.1nmspect.indexdoublenullableCa4455[-1.8/14.4]? Lick Ca4455 metal index (1)0.1nmspect.indexfloatnullableFe4531[-3.7/5.3]? Lick Fe4531 metal index (1)0.1nmspect.indexfloatnullableC24668[-6/13.7]? Lick C_2_ 4668 metal index (1)0.1nmspect.indexfloatnullableHb[-0.65/3.3]? Lick H{beta} Balmer index (1)0.1nmspect.indexfloatnullableFe5015[-1.22/7] Lick Fe5015 metal index (1)0.1nmspect.indexfloatMg1[-0.081/0.24]? Lick Mg1 metal indexmagspect.indexfloatnullableMg2[0.019/0.44]? Lick Mg2 metal indexmagspect.indexfloatnullableMgb[-2.11/6.05] Lick Mgb metal index (1)0.1nmspect.indexfloatFe5270[-1.26/4.4]? Lick Fe5270 metal index (1)0.1nmspect.indexfloatnullableFe5335Lick Fe5335 metal index (1)0.1nmspect.indexfloatFe5406Lick Fe5406 metal index (1)0.1nmspect.indexfloatFe5709Lick Fe5709 metal index (1)0.1nmspect.indexfloatFe5782? Lick Fe5782 metal index (1)0.1nmspect.indexfloatnullable[Fe/H][-2.5/0.03]? Metallicitylog(Sun)phys.abund.Zfloatnullable[M/H][-2.17/-0.0026]? Our empirically derived metallicitylog(Sun)phys.abund.Zfloatnullablee_HdA[0.6/7.31]? Lick H{delta}A Balmer index uncertainty (1)0.1nmstat.errorfloatnullablee_HdF? Lick H{delta}F Balmer index uncertainty (1)0.1nmstat.errorfloatnullablee_CN1? Lick CN1 metal index uncertaintymagstat.errorfloatnullablee_CN2? Lick CN2 metal index uncertaintymagstat.errorfloatnullablee_Ca4227? Lick Ca4227 metal index uncertainty (1)0.1nmstat.errorfloatnullablee_G4300? Lick G4300 metal index uncertainty (1)0.1nmstat.errorfloatnullablee_HgA? Lick H{gamma}A Balmer index uncertainty (1)0.1nmstat.errorfloatnullablee_Ca4455? Lick Ca4455 metal index uncertainty (1)0.1nmstat.errorfloatnullablee_Fe4531? Lick Fe4531 metal index uncertainty (1)0.1nmstat.errorfloatnullablee_C24668? Lick C_2_ 4668 metal index uncertainty (1)0.1nmstat.errorfloatnullablee_Hb? Lick H{beta} Balmer index uncertainty (1)0.1nmstat.errorfloatnullablee_Fe5335Lick Fe5335 metal index uncertainty (1)0.1nmstat.errorfloate_Fe5406Lick Fe5406 metal index uncertainty (1)0.1nmstat.errorfloate_Fe5709? Lick Fe5709 metal index uncertainty (1)0.1nmstat.errorfloatnullablee_Fe5782? Lick Fe5782 metal index uncertainty (1)0.1nmstat.errorfloatnullable