J/ApJ/711/350ivo://CDS.VizieR/J/ApJ/711/350doi:10.26093/cds/vizier.17110350CDSNorris J.E.Yong D.Gilmore G.Wyse R.F.G.2017-07-10T06:22:12Z2012-04-23T12:41:49ZCDS support team

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

cds-question@unistra.frchemical-abundancesline-intensitieschemically-peculiar-starsgiant-starsgalaxiesWe present high-resolution (R~40000), high-signal-to-noise ratio (20-90) spectra of an extremely metal-poor giant star Boo-1137 in the "ultra-faint" dwarf spheroidal galaxy (dSph) Bootes I, absolute magnitude M_V_~-6.3. We derive an iron abundance of [Fe/H]=-3.7, making this the most metal-poor star as yet identified in an ultra-faint dSph. Our derived effective temperature and gravity are consistent with its identification as a red giant in Bootes I. Abundances for a further 15 elements have also been determined. Comparison of the relative abundances, [X/Fe], with those of the extremely metal-poor red giants of the Galactic halo shows that Boo-1137 is "normal" with respect to C and N, the odd-Z elements Na and Al, the iron-peak elements, and the neutron-capture elements Sr and Ba, in comparison with the bulk of the Milky Way halo population having [Fe/H]<~-3.0. The {alpha}-elements Mg, Si, Ca, and Ti are all higher by {Delta}[X/Fe]~0.2 than the average halo values. Monte Carlo analysis indicates that {Delta}[{alpha}/Fe] values this large are expected with a probability ~0.02. The elemental abundance pattern in Boo-1137 suggests inhomogeneous chemical evolution, consistent with the wide internal spread in iron abundances we previously reported.2010ApJ...711..350Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/711/350CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/eso : ESO Science Archive Catalog (ESO, 2012)J/A+A/501/519 : Extremely metal-poor turnoff stars abundances (Bonifacio+,J/A+A/416/1117 : Abundances in the early Galaxy (Cayrel+, 2004)J/A+A/403/1105 : Extremely metal-poor giants equivalent widths (Francois+,http://www.astro.uu.se/~vald/php/vald.php : VALD www interfacehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/711/350https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/711/350http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/711/350https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/711/350https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/711/350http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/711/350GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/ApJ/711/350/table1Averaged equivalent widths, upper limits, and line-by-line abundances of Boo-1137recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIonSpecies identificationphys.atmol.ionStagecharlambdaWavelength in {AA}0.1nmem.wldoublechiLower excitation potential (1)eVphys.atmol.excitation;stat.minfloatloggfOscillator strength (1)phys.atmol.oscStrengthfloatf_loggf[a] a: loggf from VALDmeta.codecharEWEquivalent width in m{AA}0.1pmspect.line.eqWidthfloatlog(e){epsilon} abundance [log(Ion/H)+12]phys.abundfloat