J/ApJ/857/74ivo://CDS.VizieR/J/ApJ/857/74doi:10.26093/cds/vizier.18570074CDSChiti A.Frebel A.Ji A.P.Jerjen H.Kim D.Norris J.E.2019-04-08T12:56:22Z2019-03-25T14:18:29ZCDS support team

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

cds-question@unistra.frchemical-abundancesradial-velocityline-intensitiesWe present chemical abundance measurements for seven stars with metallicities ranging from [Fe/H]=-3.3 to [Fe/H]=-2.4 in the TucanaII ultra-faint dwarf galaxy (UFD), based on high-resolution spectra obtained with the MIKE spectrograph on the 6.5m Magellan-Clay Telescope. For three stars, we present detailed chemical abundances for the first time. Of those, two stars are newly discovered members of Tucana II and were selected as probable members from deep narrowband photometry of the Tucana II UFD taken with the SkyMapper telescope. This result demonstrates the potential for photometrically identifying members of dwarf galaxy systems based on chemical composition. One new star was selected from the membership catalog of Walker+ (2016, J/ApJ/819/53). The other four stars in our sample have been reanalyzed, following additional observations. Overall, six stars have chemical abundances that are characteristic of the UFD stellar population. The seventh star shows chemical abundances that are discrepant from the other Tucana II members and an atypical, higher strontium abundance than what is expected for typical UFD stars. While unlikely, its strontium abundance raises the possibility that it may be a foreground metal-poor halo star with the same systemic velocity as Tucana II. If we were to exclude this star, Tucana II would satisfy the criteria to be a surviving first galaxy. Otherwise, this star implies that Tucana II has likely experienced somewhat extended chemical evolution.2018ApJ...857...74Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/857/74CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/645/613 : Abundances of HD 221170 (Ivans+, 2006)J/ApJS/162/227 : Transition probabilities for SmII (Lawler+, 2006)J/ApJS/182/51 : Transitions of rare earth elements (Lawler+, 2009)J/ApJS/182/80 : Rare earth abundances (Sneden+, 2009)J/AN/331/474 : Abundances of metal-poor stars (Frebel, 2010)J/ApJ/708/560 : Spectroscopy of UMa II and Coma Ber (Frebel+, 2010)J/ApJ/724/341 : Nucleosynthesis of massive metal-free stars (Heger+, 2010)J/ApJ/711/350 : Metal-poor giant Boo-1137 abundances (Norris+, 2010)J/AJ/141/175 : Abundances in M15 RGB/RHB stars (Sobeck+, 2011)J/PASP/124/140 : UBVRI Hp BT and VT photonic responses (Bessell+, 2012)J/ApJ/769/57 : Equivalent widths of metal-poor stars (Frebel+, 2013)J/ApJ/763/61 : Abundances of 7 red giants of BootesI (Gilmore+, 2013)J/ApJ/779/102 : Metallicities of RGB stars in dwarf galaxies (Kirby+, 2013)J/ApJ/767/134 : Abundances of red giants in UFD galaxies (Vargas+, 2013)J/ApJ/786/74 : EW measurements of 6 Segue 1 red giants (Frebel+, 2014)J/A+A/562/A146 : Chemical abundances of 8 metal-poor stars (Ishigaki+, 2014)J/A+A/571/A47 : Linelist of CH in stellar atmospheres (Masseron+, 2014)J/ApJ/797/21 : Carbon-enhanced metal-poor stars (Placco+, 2014)J/MNRAS/440/2665 : SDSS J021933.13+200830.2 spectroscopy (Roederer+, 2014)J/AJ/147/136 : Stars of very low metal abundance. VI. (Roederer+, 2014)J/ApJ/801/125 : Carbon in red giants in GCs and dSph galaxies (Kirby+, 2015)J/ApJ/830/93 : Abundances of Ret II brightest red giant members (Ji+, 2016)J/ApJ/817/41 : Abundances of 4 metal-poor red giants in BooII (Ji+, 2016)J/ApJ/819/53 : Magellan/M2FS spectroscopy of Tuc 2 & Grus 1 (Walker+, 2016)J/ApJ/838/44 : Abundances of Tuc III brightest members (Hansen+, 2017)J/ApJ/838/83 : RVs, abundances & membership in TriII (Kirby+, 2017)J/ApJ/838/11 : Member stars in the MW satellite Tucana III (Simon+, 2017)J/ApJ/856/142 : Abundances of metal-poor stars in Sculptor (Chiti+, 2018)J/ApJ/852/99 : Abundances of 3 metal-poor stars in Hor I (Nagasawa+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/857/74https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/857/74http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/857/74https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/857/74https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/857/74http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/857/74GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/857/74/stars (Observations and stellar parameters (tables 1 and 2))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/857/74/stars?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/857/74/stars?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/857/74/stars?GETtext/xml+votable180.050000true342.9294167-58.54269440.0055555555555555566/46126 46212https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/857/74?format=asciidefaultJ/ApJ/857/74/starsObservations and stellar parameters (tables 1 and 2)SimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharprimaryRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainSlit[1] Slit sizearcsecinstr.setupfloatgmag[18.2/18.9] SkyMapper g-band magnitudemagphot.mag;em.opt.BfloatExp[155/385] Exposure timemintime.duration;obs.exposureintf_ExpFlag on Exp (1)meta.codecharS/N4500[15/17] Signal-to-noise (S/N) per pixel for 4500{AA}stat.snrintS/N6500[30/37] Signal-to-noise (S/N) per pixel for 6500{AA}stat.snrintHRV[-127/-119] Heliocentric radial velocityspect.dopplerVeloc;pos.heliocentricfloatTeff[4693/5017] Effective temperatureKphys.temperature.effectiveinte_Teff[153/227] Teff uncertaintyKstat.error;phys.temperature.effectiveintlogg[1.2/1.9] log of surface gravitylog(cm.s**-2)phys.gravityfloate_logg[0.3/0.9] logg uncertaintylog(cm.s**-2)stat.errorfloatVt[1.8/2.2] Microturbulent velocitykm/sphys.velocfloate_Vt[0.2/0.3] Vt uncertaintykm/sstat.errorfloat[Fe/H][-3.4/-2.4] Metallicityphys.abund.Zfloate_[Fe/H][0.1/0.3] [Fe/H] uncertaintystat.error;phys.abund.FefloatW16Display data from Walker+, 2016, J/ApJ/819/53meta.ref.urlcharJ/ApJ/857/74/table3Chemical abundancesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameTucana II star namemeta.id;meta.maincharprimarySpAtomic species of absorption featurephys.atmol.ionStagecharf_SpSpecies corrected (1)meta.codecharNl[1/99] Number of lines fitmeta.numberintloge[0.5/8.5] Log number abundancephys.abundfloatl_[X/H]Limit flag on [X/H]meta.code.error;phys.abundchar[X/H][-4.9/-1.6] Log abundance relative to hydrogenphys.abund;arith.zpfloatu_[X/H]Uncertainty flag on [X/H]meta.code.error;phys.abundcharl_[X/Fe]Limit flag on [X/Fe]meta.code.error;phys.abundchar[X/Fe][-2.0/1.3] Log abundance relative to ironphys.abundfloatu_[X/Fe]Uncertainty flag on [X/Fe]; see textmeta.code.error;phys.abundcharsigma[0.1/0.7]? Random uncertainties; See Table 4stat.errorfloatnullableJ/ApJ/857/74/table4UncertaintiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameTucana II star namemeta.id;meta.maincharprimarySpAtomic species of absorption featurephys.atmol.ionStagecharNl[1/99] Number of lines fitmeta.numberintRand[0.12/0.66]? Random uncertaintystat.errorfloatnullableSys[0.13/0.64]? Systematic uncertaintystat.errorfloatnullableTot[0.18/0.8]? Total uncertaintystat.errorfloatnullableJ/ApJ/857/74/table5Line measurementsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameTucana II star namemeta.id;meta.maincharlambda[3783.5/6678] Rest wavelength of absorption feature0.1nmphys.absorptionfloatSpAtomic species of absorption featurephys.atmol.ionStagecharchi[0/4.4]? Excitation potential of absorption line (1)eVphys.atmol.excitation;spect.linefloatnullableloggf[-5.7/0.7]? Oscillator strength of absorption line (1)spect.line.intensityfloatnullableEW[15.7/253]? Measured equivalent width of absorption line (1)0.1pmspect.line.eqWidthfloatnullablel_logeLimit flag on logepsilonmeta.code.errorcharloge[-2.7/6.5] Measured chemical abundance from absorption featurephys.abundfloat