J/ApJ/731/119ivo://CDS.VizieR/J/ApJ/731/119doi:10.26093/cds/vizier.17310119CDSRuhland C.Bell E.F.Rix H.-W.Xue X.-X.2018-07-04T12:11:57Z2013-08-01T12:50:56ZCDS support team

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

cds-question@unistra.frhorizontal-branch-starsradial-velocityvisible-astronomysloan-photometrymetallicityWe use a sample of blue horizontal branch (BHB) stars from the Sloan Digital Sky Survey Data Release 7 (Cat. II/294) to explore the structure of the tidal tails from the Sagittarius Dwarf Galaxy. We use a method yielding BHB star candidates with up to ~70% purity from photometry alone. The resulting sample has a distance precision of roughly 5% and can probe distances in excess of 100kpc. Using this sample, we identify a possible extension to the trailing arm at distances of 60-80kpc from the Sun with an estimated significance of at least 3.8{sigma}. Current models predict that a distant "returning" segment of the debris stream should exist, but place it substantially closer to the Sun where no debris is observed in our data. Exploiting the distance precision of our tracers, we estimate the mean line-of-sight thickness of the leading arm to be ~3kpc, and show that the two "bifurcated" branches of the debris stream differ by only 1-2kpc in distance. With a spectroscopic very pure BHB star subsample, we estimate the velocity dispersion in the leading arm, 37km/s, which is in reasonable agreement with models of Sgr disruption. We finally present a sample of high-probability Sgr BHB stars in the leading arm of Sgr, selected to have distances and velocities consistent with Sgr membership, to allow further study.2011ApJ...731..119Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/731/119CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)J/A+A/522/A88 : Photometric identification of BHB stars (Smith+, 2010)J/ApJ/684/1143 : BHB candidates in the Milky Way (Xue+, 2008)J/AJ/130/1097 : BHB stars in Century Survey Galactic Halo Project (Brown+,J/AJ/127/899 : Blue HB stars in SDSS (Sirko+, 2004)J/AJ/128/245 : M giant stars in the Sgr dwarf galaxy (Majewski+, 2004)J/ApJ/588/824 : Velocities of blue stars near (l,b)=(198,-27) (Yanny+, 2003)J/AJ/117/2308 : Spectroscopy of hot stars in the halo (Wilhelm+, 1999)J/AJ/109/1086 : VI Photometry in M54 and Sgr Dwarf Galaxy (Sarajedini+ 1995)J/AJ/108/1722 : Blue horizontal branch stars (Kinman+ 1994)http://www.sdss.org/ : SDSS home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/731/119https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/731/119http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/731/119https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/731/119https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/731/119http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/731/119GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/731/119/table5 (selected for a high probability of association with Sagittarius)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/731/119/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/731/119/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/731/119/table5?GETtext/xml+votable180.050000true149.317840.641589170.0055555555555555566/6605 6609 7290 18404 19760 19764 22717 25588 25589 25593 25839 25853 25962 26024 26048 26159 26166 26169 26200 26212 26222 26224 26243 26244 26248 26256 26266 26275 26276 26283 26288 26290 26305 26933 26947 26966 26972 26977 26988 26994 27038 27056 27244 27248 27249 30975 31145 31336 31375 31380 31386 31424 31488 36763 36765 36775https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/731/119?format=asciiOpticaldefaultJ/ApJ/731/119/table5selected for a high probability of association with SagittariusSDSSSDSS-DR7 identification (JHHMMSS.ss+DDMMSS)meta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.latdoublegmag[17/20] SDSS-DR7 g-band magnitudemagphot.mag;em.opt.Bfloatu-gu-g color indexmagphot.color;em.opt.U;em.opt.Bfloatg-rg-r color indexmagphot.color;em.opt.B;em.opt.RfloatPbhb[0/1] BHB probabilitystat.fit.goodnessfloatHRV[-83/74] Heliocentric radial velocity (1)km/sspect.dopplerVeloc;pos.heliocentricfloate_HRV[3/24] HRV uncertaintykm/sstat.errorfloatRVgal[-109/55] Radial velocity in the Galactic standard of rest (1)km/sphys.veloc;pos.galactocentricfloatFe/H[-2.4/-1]? Metallicitylog(Sun)phys.abund.Zfloatnullablee_Fe/H[0/1.1]? Fe/H uncertaintylog(Sun)stat.error;phys.abund.FefloatnullableDR7+DR9Display the SDSS-DR7 and -DR9 photometric catalogsmeta.ref.urlcharSloanDisplay the online SDSS data for this starmeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlchar