J/MNRAS/436/413ivo://CDS.VizieR/J/MNRAS/436/413doi:10.26093/cds/vizier.74360413CDSMcDonald I.Zijlstra A.A.Sloan G.C.Kerins E.J.Lagadec E.,Minniti D.Santucho M.V.Gurovich S.Dominguez Romero M.J.L.2024-08-07T20:12:06Z2014-12-22T07:18:44ZCDS support team

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

cds-question@unistra.frgalaxiesmilky-way-galaxyinfrared-photometryWe present the deepest near-infrared (ZJKs) photometry yet obtained of the Sagittarius dwarf spheroidal (Sgr dSph), using Visible and Infrared Survey Telescope for Astronomy (VISTA) to survey 11 square degrees centred on its core. We list locations and ZJKs-band magnitudes for over 2.9 million sources in the field. We discuss the isolation of the Sgr dSph from the foreground and Galactic Bulge populations, identify the Sgr dSph's horizontal branch in the near-infrared for the first time and map the density of the galaxy's stars. We present isochrones for the Sgr dSph and Bulge populations. These are consistent with the previously reported properties of the Sgr dSph core: namely that it is dominated by a population between [Fe/H]~-1dex and solar, with a significant [{alpha}/Fe] versus [Fe/H] gradient. While strong contamination from the Galactic Bulge prevents accurate measurement of the (Galactic) north side of the Sgr dSph, the dwarf galaxy can be well approximated by a roughly ovaloid projection of characteristic size 4{deg}x2{deg}, beyond which the projected stellar density is less than half that of the region surrounding the core. The galaxy's major axis is perpendicular to the Galactic Plane, as in previous studies. We find slight evidence to confirm a metallicity gradient in the Sgr dSph and use isochrones to fit a distance of 24.3+/-2.3kpc. We were unable to fully constrain the metallicity distribution of the Sgr dSph due to the Bulge contamination and strong correlation of [{alpha}/Fe] with metallicity; however, we find that metal-poor stars ([Fe/H]<~-1) make up <~29% of the Sgr dSph's upper red giant branch population. The Bulge population is best fitted by a younger population with [Fe/H] {approx} 0 and [{alpha}/Fe] {approx} 0 or slightly higher. We find no evidence for a split, peanut- or X-shaped Bulge population in this line of sight (l=5.6+/-~1{deg}, b=-14.1+/-~3{deg}).2013MNRAS.436..413Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/436/413CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/322 : UCAC4 Catalogue (Zacharias+, 2012)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)II/311 : WISE All-Sky Data Release (Cutri+ 2012)J/MNRAS/439/2618 : VISTA variables in Sagittarius dSph (McDonald+, 2014)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/436/413https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/436/413http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/436/413https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/436/413https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/436/413http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/436/413GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/436/413/table1 (Details of the identified sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/436/413/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/436/413/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/436/413/table1?GETtext/xml+votable180.050000true280.05335-31.41010.0055555555555555565/11967 12008-12010 6/28756-28757 28759 28928-28930 47861 47863 48010-48011 48014-48015 48044 480468.643406281242892e-20 2.393642124494231e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/436/413?format=asciiInfrareddefaultJ/MNRAS/436/413/table1Details of the identified sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintVSgrSource Name (HHMMSSss+DDMMSSs)meta.id;meta.maincharRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainindexedDEJ2000Declination (J2000)degpos.eq.dec;meta.mainindexedZmag[9.4/23.6]? VISTA Z magnitudemagphot.mag;em.opt.Ifloatnullablee_Zmag? rms uncertainty on Zmagmagstat.error;phot.mag;em.opt.IfloatnullableJmag[9.2/23.1]? VISTA J magnitudemagphot.mag;em.IR.Jfloatnullablee_Jmag? rms uncertainty on Jmagmagstat.error;phot.mag;em.IR.JfloatnullableKsmag[8.4/19.9]? VISTA Ks magnitudemagphot.mag;em.IR.Kfloatnullablee_Ksmag? rms uncertainty on Ksmagmagstat.error;phot.mag;em.IR.KfloatnullableUCAC4? UCAC4 cross-identification (I/322)meta.id.crosschardist1Distance between source and closest UCAC4 (1)arcsecpos;arith.difffloat2MASS? 2MASS cross-identification (II/246) (HHMMSSss+DDMMSSA) (1)meta.id.crosschardist2Distance between source and closest 2MASS (1)arcsecpos;arith.difffloatWISE? WISE cross-identification (II/311) (JHHMMSS.ss+DDMMSS.s) (1)meta.id.crosschardist3Distance between source and closest WISE (1)arcsecpos;arith.difffloat