J/ApJ/756/79ivo://CDS.VizieR/J/ApJ/756/79doi:10.26093/cds/vizier.17560079CDSSand D.J.Strader J.Willman B.Zaritsky D.McLeod B.Caldwell N.,Seth A.Olszewski E.2014-05-26T21:16:03Z2014-05-05T11:48:00ZCDS support team

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

cds-question@unistra.frgalaxiesinfrared-photometryvisible-astronomyphotometryWe present deep wide-field photometry of three recently discovered faint Milky Way (MW) satellites: Leo V, Pisces II, and Canes Venatici II. Our main goals are to study the structure and star formation history of these dwarfs; we also search for signs of tidal disturbance. The three satellites have similar half-light radii (~60-90pc) but a wide range of ellipticities. Both Leo V and CVn II show hints of stream-like overdensities at large radii. An analysis of the satellite color-magnitude diagrams shows that all three objects are old (>10Gyr) and metal-poor ([Fe/H]~-2), though neither the models nor the data have sufficient precision to assess when the satellites formed with respect to cosmic reionization. The lack of an observed younger stellar population (<~10Gyr) possibly sets them apart from the other satellites at Galactocentric distances >~150kpc. We present a new compilation of structural data for all MW satellite galaxies and use it to compare the properties of classical dwarfs to the ultra-faints. The ellipticity distribution of the two groups is consistent at the ~2{sigma} level. However, the faintest satellites tend to be more aligned toward the Galactic Center, and those satellites with the highest ellipticity (>~0.4) have orientations ({Delta}{theta}_GC_) in the range 20{deg}<~{Delta}{theta}_GC_<~40{deg}. This latter observation is in rough agreement with predictions from simulations of dwarf galaxies that have lost a significant fraction of their dark matter halos and are being tidally stripped.2012ApJ...756...79Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/756/79CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/144/4 : Dwarf galaxies in the Local Group (McConnachie+, 2012)J/AJ/142/88 : Segue 3 photometric and kinematic data (Fadely+, 2011)J/ApJ/718/530 : Leo IV g- and r-band photometry (Sand+, 2010)J/ApJ/710/1664 : BV photometry in Leo IV and Leo V dSphs (de Jong+, 2010)J/ApJ/694/L144 : Spectroscopic study of Leo V dSph (Walker+, 2009)J/MNRAS/360/185 : VI photometry of the Leo II galaxy (Bellazzini+, 2005)J/MNRAS/354/708 : Leo I VI photometry (Bellazzini+, 2004)J/AJ/126/2840 : BVI CCD photometry of Sextans dSph galaxy (Lee+, 2003)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/756/79https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/756/79http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/756/79https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/756/79https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/756/79http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/756/79GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/756/79/table2 (Leo V gr-photometry with Megacam)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/756/79/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/756/79/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/756/79/table2?GETtext/xml+votable180.050000true172.833952.19777610.005555555555555556Cone search capability for table J/ApJ/756/79/table3 (Pisces II gr-photometry with Megacam)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/756/79/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/756/79/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/756/79/table3?GETtext/xml+votable180.050000true344.599975.95898190.005555555555555556Cone search capability for table J/ApJ/756/79/table4 (CVn II VI-photometry with Subaru)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/756/79/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/756/79/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/756/79/table4?GETtext/xml+votable180.050000true194.2873634.312270.0055555555555555565/2692 6750 6/18923 18926 19265 192682.191031165672097e-19 4.752121017816135e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/756/79?format=asciiOpticalInfrareddefaultJ/ApJ/756/79/table2Leo V gr-photometry with Megacame_rmag[0.01/0.6] Uncertainty in rmagmagstat.error;phot.mag;em.opt.RfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqRunning sequence number (starting at "0")meta.id;meta.mainintRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainindexedDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainindexedgmag[14.5/28] CFHT/Megacam g band magnitude (1)magphot.mag;em.opt.Bfloate_gmag[0.01/0.6] Uncertainty in gmagmagstat.error;phot.mag;em.opt.BfloatAg[0.08/0.3] Schlegel et al. 1998ApJ...500..525S g-band extinctionmagphot.magfloatrmag[15/27.6] CFHT/Megacam r band magnitude (1)magphot.mag;em.opt.RfloatAr[0.06/0.3] Schlegel et al. 1998ApJ...500..525S r-band extinctionmagphot.magfloatInstPhotometry source (2)meta.id;instrchardJ10Cross-match with de Jong et al. 2010, Cat. J/ApJ/710/1664, within 1.5"meta.ref.urlintnullableJ/ApJ/756/79/table3Pisces II gr-photometry with MegacamrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqRunning sequence number (starting at "0")meta.id;meta.mainintRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.maingmag[14.5/28] CFHT/Megacam g band magnitude (1)magphot.mag;em.opt.Bfloate_gmag[0.01/0.6] Uncertainty in gmagmagstat.error;phot.mag;em.opt.BfloatAg[0.08/0.3] Schlegel et al. 1998ApJ...500..525S g-band extinctionmagphot.magfloatrmag[15/27.6] CFHT/Megacam r band magnitude (1)magphot.mag;em.opt.Rfloate_rmag[0.01/0.6] Uncertainty in rmagmagstat.error;phot.mag;em.opt.RfloatAr[0.06/0.3] Schlegel et al. 1998ApJ...500..525S r-band extinctionmagphot.magfloatInstPhotometry source (2)meta.id;instrcharJ/ApJ/756/79/table4CVn II VI-photometry with SubaruInstPhotometry source (2)meta.id;instrcharDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainindexedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[0/42490] Running sequence numbermeta.id;meta.mainintRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainindexedVmag[14.7/27.4] Subaru V band magnitude (1)magphot.mag;em.opt.Vfloate_Vmag[0.01/0.6] Uncertainty in Vmagmagstat.error;phot.mag;em.opt.VfloatAv[0.03/0.04] Schlegel et al. 1998ApJ...500..525S V-band extinctionmagphot.magfloatImag[15/27] Subaru I band magnitude (1)magphot.mag;em.opt.Ifloate_Imag[0.01/0.6] Uncertainty in Imagmagstat.error;phot.mag;em.opt.IfloatAi[0.01/0.02] Schlegel et al. 1998ApJ...500..525S I-band extinctionmagphot.magfloat