J/MNRAS/485/2010ivo://CDS.VizieR/J/MNRAS/485/2010doi:10.26093/cds/vizier.74852010CDSGregory A.L.Collins M.L.M.Read J.I.Irwin M.J.Ibata R.A.,Martin N.F.McConnachie A.W.Weisz D.R.2024-08-19T20:17:15Z2022-11-17T14:15:11ZCDS support team

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

cds-question@unistra.frgalaxiesvisible-astronomyphotometryspectroscopyWe present new FLAMES+GIRAFFE spectroscopy of 36 member stars in the isolated Local Group dwarf spheroidal galaxy Tucana. We measure a systemic velocity for the system of v_Tuc_=216.7^+2.9^_-2.8_km/s, and a velocity dispersion of {sigma}_v,Tuc_=14.4^+2.8^_-2.3_km/s. We also detect a rotation gradient of dv_r_/d{Chi}=7.6^+4.2^_-4.3_km/s/kpc, which reduces the systemic velocity to v_Tuc_=215.2^+2.8^_-2.7_km/s and the velocity dispersion to {sigma}_v,Tuc_=13.3^+2.7^_-2.3_km/s. We perform Jeans modelling of the density profile of Tucana, using the line-of-sight velocities of the member stars. We find that it favours a high central density consistent with 'pristine' subhaloes in {Lambda} cold dark matter, and a massive dark matter halo (~10^10^M_{sun}_) consistent with expectations from abundance matching. Tucana appears to be significantly more centrally dense than other isolated Local Group dwarfs, making it an ideal laboratory for testing dark matter models.2019MNRAS.485.2010Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/485/2010CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/485/2010https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/485/2010http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/485/2010https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/485/2010https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/485/2010http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/485/2010GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/485/2010/table2 (Details of all successfully reduced targets observed with FLAMES+GIRAFFE)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/485/2010/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/485/2010/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/485/2010/table2?GETtext/xml+votable180.050000true340.5952-64.20660.005555555555555556Cone search capability for table J/MNRAS/485/2010/table3 (Details of the 36 identified members of Tucana observed with FLAMES+GIRAFFE)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/485/2010/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/485/2010/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/485/2010/table3?GETtext/xml+votable180.050000true340.3689-64.41160.0055555555555555566/45423https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/485/2010?format=asciiOpticaldefaultJ/MNRAS/485/2010/table2Details of all successfully reduced targets observed with FLAMES+GIRAFFESimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDObject identifiermeta.id;meta.mainintHVLine-of-sight heliocentric velocitykm/sspect.dopplerVeloc;pos.heliocentricfloate_HVError on HVkm/sstat.errorfloatRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.maingmagg-band magnitude from Magellan/MegaCam imagingmagphot.mag;em.opt.Bfloatimagi-band magnitude from Magellan/MegaCam imagingmagphot.mag;em.opt.IfloatSNRSignal to noise ratiopixel**-1stat.snrfloatMember[Y/N] Determination of Tucana membershipmeta.code.membercharOName? ID of counterpart in Fraternali et al. (2009A&A...499..121F) (F09) data set, [FTI2009] NN in Simbadmeta.idintnullableHVF09? Velocity of F09 counterpart (Fraternali et al. 2009A&A...499..121F)km/sphys.veloc;pos.heliocentricfloatnullablee_HVF09? Error on HVF09km/sstat.errorfloatnullableJ/MNRAS/485/2010/table3Details of the 36 identified members of Tucana observed with FLAMES+GIRAFFESimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDObject identifiermeta.id;meta.mainintHVLine-of-sight heliocentric velocitykm/sspect.dopplerVeloc;pos.heliocentricfloate_HVError on HVkm/sstat.errorfloatRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainSepOn-sky separation of the object from the central coordinates of Tucana (22 41 49.6, -64 25 10)arcsecpos.angDistancefloatgmagg-band magnitude from Magellan/MegaCam imagingmagphot.mag;em.opt.Bfloatimagi-band magnitude from Magellan/MegaCam imagingmagphot.mag;em.opt.IfloatSNRSignal to noise ratiopixel**-1stat.snrfloat