J/A+A/465/357ivo://CDS.VizieR/J/A+A/465/357doi:10.26093/cds/vizier.34650357CDSFaria D.Feltzing S.Lundstroem I.Gilmore G.Wahlgren G.M.,Ardeberg A.Linde P.2017-10-09T13:34:39Z2007-12-31T18:51:59ZCDS support team

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

cds-question@unistra.frgalaxiesvisible-astronomymedium-band-photometrymetallicityIn this paper we demonstrate how Stroemgren uvby photometry can be efficiently used to: 1. identify red giant branch stars that are members in a dwarf spheroidal galaxy; 2. derive age-independent metallicities for the same stars and quantify the associated errors. Stroemgren uvby photometry in a 11'x22' field centered on the Draco dwarf spheroidal galaxy was obtained using the Isaac Newton Telescope on La Palma. Members of the Draco dSph galaxy were identified using the surface gravity sensitive c1 index which discriminates between red giant and dwarf stars. Thus enabling us to distinguish the (red giant branch) members of the dwarf spheroidal galaxy from the foreground dwarf stars in our galaxy. The method is evaluated through a comparison of our membership list with membership classifications in the literature based on radial velocities and proper motions. The metallicity sensitive m1 index was used to derive individual and age-independent metallicities for the members of the Draco dSph galaxy. The derived metallicities are compared to studies based on high resolution spectroscopy and the agreement is found to be very good.2007A&A...465..357Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/465/357CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/110/2131 : M/L for Draco and UMi. I. (Armandroff+ 1995)J/AJ/121/841 : RV photometry of Draco dwarf spheroidal galaxy (Piatek+, 2001)J/AJ/123/2511 : RV photometry of Draco dwarf spheroidal galaxy (Piatek+, 2002)J/ApJS/145/245 : SDSS stars in Draco dwarf spheroidal galaxy (Rave+, 2003)J/AJ/127/861 : RR Lyrae in Draco dSph (Bonanos+, 2004)J/A+A/442/165 : Draco dSph late-type stars IJKs photometry (Cioni+, 2005)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/465/357https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/465/357http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/465/357https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/465/357https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/465/357http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/465/357GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/465/357/table2 (List of the photometry used for the standard stars (from Schuster & Nissen, 1988A&AS...73..225S))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/465/357/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/465/357/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/465/357/table2?GETtext/xml+votable180.050000true77.5086581-7.07175970.005555555555555556Cone search capability for table J/A+A/465/357/table6 (Draco RGB stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/465/357/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/465/357/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/465/357/table6?GETtext/xml+votable180.050000true260.391065857.94487440.0055555555555555566/4875 4901 4905 5160 6256 8873 10183 15707 22048 22118 22793 25298 25554 25723 25835 25839 25889 26158 26187 26728 26827 27991 28483 29490 29593 29596 30233 30236 30744 30939 40410 40750 40769 40908 40931 44151 44281 44447 44775 44816 44910 44951https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/465/357?format=asciiOpticaldefaultJ/A+A/465/357/table2List of the photometry used for the standard stars (from Schuster & Nissen, 1988A&AS...73..225S)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordinty0Dereddened Stroemgren y magnitudemagphot.mag;em.opt.Vfloat(b-y)0Dereddened Stroemgren b-y colour indexmagphot.color;em.opt.B;em.opt.Vfloat(m1)0Dereddened Stroemgren m1 indexmagphot.color.reddFreefloat(c1)0Dereddened Stroemgren c1 indexmagphot.colorfloatSimbadSimbad column added by the CDSchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainNameNamemeta.id;meta.maincharJ/A+A/465/357/table6Draco RGB starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[FFL2007]Sequential numbermeta.recordintONameStetson number (1)meta.idcharxposX pixel position on the CCDpixpos.cartesian.x;instr.detdoubleyposY pixel position on the CCDpixpos.cartesian.y;instr.detdoubleoRAOffset in right ascension (2)arcminpos.eq.ra;arith.diffdoubleoDEOffset in declination (2)arcminpos.eq.dec;arith.diffdoubleymagStroemgren y magnitude (3)magphot.mag;em.opt.Vfloate_ymagrms uncertainty on ymagmagstat.error;phot.mag;em.opt.VfloatbmagStroemgren b magnitude (3)magphot.mag;em.opt.Bfloate_bmagrms uncertainty on bmagmagstat.error;phot.mag;em.opt.BfloatumagStroemgren u magnitude (3)magphot.mag;em.opt.UfloatvmagStroemgren v magnitude (3)magphot.mag;em.opt.Bfloate_vmagrms uncertainty on vmagmagstat.error;phot.mag;em.opt.Bfloate_umagrms uncertainty on umagmagstat.error;phot.mag;em.opt.Ufloat[Fe/H]Metallicity derived in this paper using the m1 indexlog(Sun)meta.code;phys.abund.Zfloate_[Fe/H]rms uncertainty on [Fe/H]log(Sun)stat.error;phys.abund.FefloatPmem? Membership probability (4)meta.code.memberfloatnullableRV? Radial velocity from Kleyna et al. (2002, Cat. <J/MNRAS/330/792>)km/sspect.dopplerVeloc;pos.heliocentricfloatnullable_RAPositions computed from (Xpos,Ypos) by VizieR (right ascension part)degpos.eq.ra;meta.main_DEPositions computed from (Xpos,Ypos) by VizieR (declination part)degpos.eq.dec;meta.main