J/ApJ/779/102ivo://CDS.VizieR/J/ApJ/779/102doi:10.26093/cds/vizier.17790102CDSKirby E.N.Cohen J.G.Guhathakurta P.Cheng L.Bullock J.S.,Gallazzi A.2020-07-21T06:56:29Z2015-06-10T13:53:53ZCDS support team

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

cds-question@unistra.frgalaxiesgiant-starsmetallicityspectroscopyWe present spectroscopic metallicities of individual stars in seven gas-rich dwarf irregular galaxies (dIrrs), and we show that dIrrs obey the same mass-metallicity relation as the dwarf spheroidal (dSph) satellites of both the Milky Way and M31: Z_{star}_{propto}M_{star}_^0.30+/-0.02^. The uniformity of the relation is in contradiction to previous estimates of metallicity based on photometry. This relationship is roughly continuous with the stellar mass-stellar metallicity relation for galaxies as massive as M_*_=10^12^M_{sun}_. Although the average metallicities of dwarf galaxies depend only on stellar mass, the shapes of their metallicity distributions depend on galaxy type. The metallicity distributions of dIrrs resemble simple, leaky box chemical evolution models, whereas dSphs require an additional parameter, such as gas accretion, to explain the shapes of their metallicity distributions. Furthermore, the metallicity distributions of the more luminous dSphs have sharp, metal-rich cut-offs that are consistent with the sudden truncation of star formation due to ram pressure stripping.2013ApJ...779..102Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/779/102CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)J/MNRAS/439/1015 : Velocities of RGB stars in LG dwarf galaxies (Kirby+, 2014)J/A+A/572/A88 : Measured EWs for Fornax RGB stars (Lemasle+, 2014)J/ApJ/770/16 : Spectroscopic members of Segue 2 galaxy (Kirby+, 2013)J/ApJ/768/172 : Kinematic analysis of RGB in M31 dSphs (Collins+, 2013)J/ApJ/767/134 : Abundances of RGB stars in UFD galaxies (Vargas+, 2013)J/ApJ/765/140 : Stacked spectra of SDSS star forming gal. (Andrews+, 2013)J/AJ/144/4 : Properties of dwarf galaxies in the LG (McConnachie+, 2012)J/ApJ/752/45 : SPLASH: spectroscopy of M31 satellites (Tollerud+, 2012)J/ApJ/751/46 : Spectroscopic observations in VV124 (Kirby+, 2012)J/MNRAS/421/2998 : NGC 6822 Cepheids JHKs light curves (Feast+, 2012)J/MNRAS/414/3492 : JHKs photometry of Sculptor dSph galaxy (Menzies+, 2011)J/MNRAS/411/1013 : CaII triplet in Sextans dSph galaxy (Battaglia+, 2011)J/ApJ/726/108 : Dispersion-supported stellar systems (Tollerud+, 2011)J/ApJS/191/352 : Abundances in stars of MW dwarf satellites (Kirby+, 2010)J/ApJ/718/530 : Leo IV g- and r-band photometry (Sand+, 2010)J/ApJ/711/361 : Local Group dE galaxies. II. (Geha+, 2010)J/ApJ/705/328 : Abundance measurements in Sculptor dSph (Kirby+, 2009)J/ApJS/182/216 : Surface photometry of Virgo ellipticals (Kormendy+, 2009)J/AJ/137/3100 : Radial velocities of 4 dSph galaxies (Walker+, 2009)J/ApJ/682/1217 : Abundances in red giants in globular clusters (Kirby+, 2008)J/ApJ/657/241 : Spectroscopy of Leo I red giants (Koch+, 2007)J/A+A/467/1025 : JHK photometry of Fornax RGB stars (Gullieuszik+, 2007)J/AJ/133/2393 : UBVRI phot. in 7 Local Group dwarfs galaxies (Massey+, 2007)J/A+A/459/423 : VI and [Fe/H] of Fornax dSph RGB stars (Battaglia+, 2006)J/AJ/131/332 : Velocities of individual stars in NGC 205 (Geha+, 2006)J/AJ/128/16 : HIPASS Bright Galaxy Catalog (Koribalski+, 2004)J/AJ/127/840 : VRI photometry of Fornax red giants (Pont+, 2004)J/A+A/407/423 : Coma cluster early-type galaxies. III. (Mehlert+, 2003)J/MNRAS/327/918 : CaII in extragalactic red giants (Tolstoy+, 2001)J/AJ/118/1671 : Fornax cluster 4 VI photometry (Buonanno+, 1999)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/779/102https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/779/102http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/779/102https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/779/102https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/779/102http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/779/102GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/779/102/table1 (Dwarf galaxy sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/779/102/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/779/102/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/779/102/table1?GETtext/xml+votable180.050000true39.99583-34.449170.005555555555555556Cone search capability for table J/ApJ/779/102/table3 (Metallicity catalog for all of the individual member stars in the dIrrs and the MW satellites)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/779/102/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/779/102/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/779/102/table3?GETtext/xml+votable180.050000true14.8399167-33.71608330.0055555555555555566/619 2216 2272 2604 2611 2628 2668 2676 2709 2746 2774 2777 2852 4410 5287 5293 6021 6023 6032 7265 7416 7417 10181 10183 10189 10444 10446 10769 10771 11691 14149 18041 19990 26980 27207 27574 27580 28136 28361 29716 29718 31692 35549 35720 35969 48942 48943https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/779/102?format=asciidefaultJ/ApJ/779/102/table1Dwarf galaxy sampleSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHostHost of dwarf galaxies (MW:Milky Way; LG:local group or M31)meta.id.parentcharTypeGalaxy type (dSph/dE or dIrr)src.morph.typecharNameDwarf galaxy namemeta.id;meta.maincharf_NameControversial galaxy classification (1)meta.codecharNstNumber of stars with measured metallicity (table3)meta.numberintnullableRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainlogM*[3/8.7] Log of stellar masslog(solMass)phys.massfloatDMW[38/1367]? Distance to Milky Waykpcpos.distance;pos.galactocentricintnullableDM31[40/1395]? Distance to M31kpcpos.distanceintnullablel_Vrot/sigLimit flag on Vrot/sigmeta.code.errorcharVrot/sig[0.3/8.1]? Ratio of rotation velocity to velocity dispersionphys.veloc;arith.difffloatnullableMHI/M*[0/3.7]? HI mass to stellar mass ratiophys.mass;arith.ratiofloatnullablef_MHI/M*[b] HI along line of sight only (2)meta.codecharGalAbbreviated name of dwarf galaxy as in table 3 (column added by CDS)meta.idcharNobsNumber of new spectroscopic observations for this galaxy (table2)meta.numberintnullableNEDNED column added by the CDSmeta.ref.urlcharJ/ApJ/779/102/table3Metallicity catalog for all of the individual member stars in the dIrrs and the MW satellitesSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalDwarf galaxy abbreviated namemeta.id.parentcharNameStar namemeta.id;meta.maincharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainn_mag1? First filter (B, V, g or M) (1)meta.code;instr.filtercharmag1[16.7/26.4]? Extinction-corrected magnitude in Filt1magphot.magfloatnullablee_mag1[0/0.9]? Uncertainty in mag1magstat.errorfloatnullablen_mag2Second filter (V, R, I, i, r or T2) (1)meta.code;instr.filtercharmag2[15.2/23.7] Extinction-corrected magnitude in Filt2magphot.magfloate_mag2[0/0.3] Uncertainty in mag2magstat.errorfloatn_mag3? Third filter (I or i) (1)meta.code;instr.filtercharmag3[15.8/22.6]? Extinction-corrected magnitude in Filt3magphot.magfloatnullablee_mag3[0.001/1.1]? Uncertainty in mag3magstat.errorfloatnullableTeff[3500/6782] Effective temperatureKphys.temperature.effectiveinte_Teff[0/479] Uncertainty in TeffKstat.error;phys.temperature.effectiveintlog(g)[0/3.6] Log of surface gravitylog(cm.s**-2)phys.gravityfloate_log(g)[0.02/0.8] Uncertainty in log(g)log(cm.s**-2)stat.errorfloatvt[1.2/2.2] Microturbulent velocity {xi}km/sphys.velocfloat[Fe/H][-4/-0.01] Iron abundance relative to the Sunlog(Sun)phys.abund.Fefloate_[Fe/H][0.1/1] Uncertainty in [Fe/H]log(Sun)stat.error;phys.abund.FefloatKCatSources within 2" from Kirby+ (2014, J/MNRAS/439/1015; 2012, J/ApJ/751/46; 2013, J/ApJ/770/16; 2010, J/ApJS/191/352 and 2009, J/ApJ/705/328)meta.ref.urlintnullableJ/ApJ/779/102/table2DEIMOS observations of the 7 dwarf irregular galaxies (dIrrs)SlitSlitmaskmeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameGalaxy namemeta.id;meta.maincharn_Name[ab] Note about previous observations (1)meta.notecharN[64/199] Number of red giant candidatesmeta.numberintExp[1/10.3] Exposure timehtime.duration;obs.exposurefloatDateUT date of observationtime.epoch;obsnullableSeeing[0.4/1.2] Seeingarcsecinstr.obsty.seeingfloatIExpIndividual exposuresstime.expochar