J/ApJ/863/25ivo://CDS.VizieR/J/ApJ/863/25doi:10.26093/cds/vizier.18630025CDSMutlu-Pakdil B.Sand D.J.Carlin J.L.Spekkens K.Caldwell N.,Crnojevic D.Hughes A.K.Willman B.Zaritsky D.2019-11-27T13:30:41Z2019-08-30T14:15:21ZCDS support team

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

cds-question@unistra.frgalaxiesphotometryvisible-astronomyextinctionWe present deep Magellan/Megacam stellar photometry of four recently discovered faint Milky Way satellites: Sagittarius II (Sgr II), Reticulum II (Ret II), Phoenix II (Phe II), and Tucana III (Tuc III). Our photometry reaches ~2-3 magnitudes deeper than the discovery data, allowing us to revisit the properties of these new objects (e.g., distance, structural properties, luminosity measurements, and signs of tidal disturbance). The satellite color-magnitude diagrams show that they are all old (~13.5Gyr) and metal poor ([Fe/H]<~-2.2). Sgr II is particularly interesting, as it sits in an intermediate position between the loci of dwarf galaxies and globular clusters in the size-luminosity plane. The ensemble of its structural parameters is more consistent with a globular cluster classification, indicating that Sgr II is the most extended globular cluster in its luminosity range. The other three satellites land directly on the locus defined by Milky Way ultra-faint dwarf galaxies of similar luminosity. Ret II is the most elongated nearby dwarf galaxy currently known for its luminosity range. Our structural parameters for Phe II and Tuc III suggest that they are both dwarf galaxies. Tuc III is known to be associated with a stellar stream, which is clearly visible in our matched-filter stellar density map. The other satellites do not show any clear evidence of tidal stripping in the form of extensions or distortions. Finally, we also use archival HI data to place limits on the gas content of each object.2018ApJ...863...25Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/863/25CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)J/MNRAS/390/1437 : Stellar streams in Andromeda (M31) (Chapman+, 2008)J/ApJ/704/898 : Photometry of the Hercules dwarf galaxy (Sand+, 2009)J/ApJ/718/530 : Leo IV g- and r-band photometry (Sand+, 2010)J/AJ/144/4 : Dwarf galaxies in the Local Group (McConnachie+, 2012)J/ApJ/756/79 : Opt. photometry in 3 Local Group dwarf gal. (Sand+, 2012)J/ApJ/809/146 : SDSS-DR8 isolated low-mass galaxies (Bradford+, 2015)J/ApJ/803/63 : gr photometry of stars in Kim 2 (Kim+, 2015)J/ApJ/808/95 : Spectroscopy of Reticulum II (Simon+, 2015)J/ApJ/808/108 : M2FS stellar spectroscopy of Reticulum 2 (Walker+, 2015)J/AJ/151/82 : The 4 brightest red giants in Ret 2 (Roederer+, 2016)J/ApJ/838/83 : RVel, abundances & membership in TriII (Kirby+, 2017)J/ApJ/838/11 : Member stars in the MW satellite Tucana III (Simon+, 2017)J/A+A/620/A155 : Gaia proper motions of 7 UFD galaxies (Massari+, 2018)J/AJ/157/12 : Star clusters, associations & cand. in the MW (Bica+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/863/25https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/863/25http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/863/25https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/863/25https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/863/25http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/863/25GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/863/25/table3 (Ret II photometry in the DES photometric system)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/863/25/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/863/25/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/863/25/table3?GETtext/xml+votable180.050000true53.56018-54.237830.005555555555555556Cone search capability for table J/ApJ/863/25/table4 (Phe II photometry in the DES photometric system)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/863/25/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/863/25/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/863/25/table4?GETtext/xml+votable180.050000true354.64833-54.60238610.005555555555555556Cone search capability for table J/ApJ/863/25/table5 (Tuc III photometry in the DES photometric system)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/863/25/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/863/25/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/863/25/table5?GETtext/xml+votable180.050000true358.7535-59.79529610.005555555555555556Cone search capability for table J/ApJ/863/25/table6 (Structural properties of the Milky Way satellites)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/863/25/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/863/25/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/863/25/table6?GETtext/xml+votable180.050000true298.1647083-22.06505280.005555555555555556Cone search capability for table J/ApJ/863/25/table2 (Sgr II photometry in the PS1 photometric system)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/863/25/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/863/25/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/863/25/table2?GETtext/xml+votable180.050000true297.93523-22.26225310.0055555555555555566/33626 33627 46144 46145 46168 46169 48771 48774 48777 487802.7756605430020253e-19 4.973527819473193e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/863/25?format=asciiOpticaldefaultJ/ApJ/863/25/table3Ret II photometry in the DES photometric systemrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[0/57846] Sequential star numbermeta.id;meta.mainintRAJ2000Right Ascension (J2000)degpos.eq.ra;meta.mainindexedDEJ2000Declination (J2000)degpos.eq.dec;meta.mainindexedgmag[16.3/27.1] Clay/Megacam g band AB photometry (1)magphot.mag;em.opt.Bfloate_gmag[0/0.6] Uncertainty in gmagmagstat.error;phot.mag;em.opt.BfloatAg[0.03/0.06] Extinction in the g band (2)magphys.absorptionfloatrmag[15.5/26.1] Clay/Megacam r band AB photometry (1)magphot.mag;em.opt.Rfloate_rmag[0/0.5] Uncertainty in rmagmagstat.error;phot.mag;em.opt.RfloatAr[0.02/0.04] Extinction in the r band (2)magphys.absorptionfloatJ/ApJ/863/25/table4Phe II photometry in the DES photometric systemrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[0/57846] Sequential star numbermeta.id;meta.mainintRAJ2000Right Ascension (J2000)degpos.eq.ra;meta.mainindexedDEJ2000Declination (J2000)degpos.eq.dec;meta.mainindexedgmag[16.3/27.1] Clay/Megacam g band AB photometry (1)magphot.mag;em.opt.Bfloate_gmag[0/0.6] Uncertainty in gmagmagstat.error;phot.mag;em.opt.BfloatAg[0.03/0.06] Extinction in the g band (2)magphys.absorptionfloatrmag[15.5/26.1] Clay/Megacam r band AB photometry (1)magphot.mag;em.opt.Rfloate_rmag[0/0.5] Uncertainty in rmagmagstat.error;phot.mag;em.opt.RfloatAr[0.02/0.04] Extinction in the r band (2)magphys.absorptionfloatJ/ApJ/863/25/table5Tuc III photometry in the DES photometric systemrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[0/57846] Sequential star numbermeta.id;meta.mainintRAJ2000Right Ascension (J2000)degpos.eq.ra;meta.mainindexedDEJ2000Declination (J2000)degpos.eq.dec;meta.mainindexedgmag[16.3/27.1] Clay/Megacam g band AB photometry (1)magphot.mag;em.opt.Bfloate_gmag[0/0.6] Uncertainty in gmagmagstat.error;phot.mag;em.opt.BfloatAg[0.03/0.06] Extinction in the g band (2)magphys.absorptionfloatrmag[15.5/26.1] Clay/Megacam r band AB photometry (1)magphot.mag;em.opt.Rfloate_rmag[0/0.5] Uncertainty in rmagmagstat.error;phot.mag;em.opt.RfloatAr[0.02/0.04] Extinction in the r band (2)magphys.absorptionfloatJ/ApJ/863/25/table6Structural properties of the Milky Way satellitesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of the MW satellitemeta.id;instr.obstycharRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.maine_RAJ2000[3/36.7] RA uncertaintysstat.error;pos.eq.rafloatDEJ2000[22/59] Degree of declination (J2000)pos.eq.dec;meta.maine_DEJ2000[2.2/26] DE uncertaintyarcsecstat.error;pos.eq.decfloatm-M[16.8/19.6] Distance modulusmagphot.mag.distModfloate_m-M[0.1/0.2] m-M uncertaintymagstat.errorfloatE(B-V)[0.01/0.2] Color excessmagphot.color.excessfloatDist[22.9/84.1] Distancekpcpos.distance;pos.heliocentricfloate_Dist[0.9/8] Dist uncertaintykpcstat.errorfloatN*[162/1502] Number of stars brighter than r=24mag (1)meta.numberintVMag[-5.2/-1.3] Absolute V-band magnitudemagphot.mag;em.opt.Vfloate_VMag[0.1/0.4] VMag uncertaintymagstat.error;phot.mag;em.opt.Vfloatrh[1.5/6.3] Half-light radius in arcminarcminphys.angSize;srcfloate_rh[0.1/1.2] rh uncertaintyarcminstat.errorfloatrhpc[32/58] Half-light radius in pcpcphys.size.radiusinte_rhpc[1/8] rhpc uncertaintypcstat.errorintl_eLimit flag on emeta.code.errorchare[0.1/0.6] Ellipticitysrc.ellipticityfloate_e[0.1]? e uncertaintystat.errorfloatnullablePA[25/156]? Position angledegpos.posAngintnullablef_PAu: unconstrainedmeta.codechare_PA[2/38]? PA uncertaintydegstat.errorintnullablelogJ[18.2/19.2] 0.5{deg} J-factorGeV**2.cm**-5stat.fit.paramfloatMHI[210/1400] 5{sigma} upper limit on the HI masssolMassphys.mass;stat.maxintM/L[0.2/2] MHI to L_V_ ratiosolMass/solLumphys.composition.massLightRatiofloatNEDNED column added by the CDSmeta.ref.urlcharJ/ApJ/863/25/table2Sgr II photometry in the PS1 photometric systemrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[0/61673] Sequential star number in Sgr IImeta.id;meta.mainintRAJ2000[297.9/298.4] Right Ascension (J2000)degpos.eq.ra;meta.mainindexedDEJ2000[-22.3/-21.8] Declination (J2000)degpos.eq.dec;meta.mainindexedgmag[17.73/27.36] Clay/Megacam g band AB photometry (1)magphot.mag;em.opt.Bfloate_gmag[0.0/0.54] Uncertainty in gmagmagstat.error;phot.mag;em.opt.BfloatAg[0.32/0.37] Extinction in the g band (2)magphys.absorptionfloatrmag[17.13/26.27] Clay/Megacam r AB band photometry (1)magphot.mag;em.opt.Rfloate_rmag[0.0/0.54] Uncertainty in rmagmagstat.error;phot.mag;em.opt.RfloatAr[0.23/0.27] Extinction in the r band (2)magphys.absorptionfloat