J/ApJ/768/172ivo://CDS.VizieR/J/ApJ/768/172doi:10.26093/cds/vizier.17680172CDSCollins M.L.M.Chapman S.C.Rich R.M.Ibata R.A.Martin N.F.,Irwin M.J.Bate N.F.Lewis G.F.Penarrubia J.Arimoto N.Casey C.M.,Ferguson A.M.N.Koch A.McConnachie A.W.Tanvir N.2017-06-27T06:37:40Z2015-01-08T11:12:28ZCDS support team

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

cds-question@unistra.frinfrared-photometryvisible-astronomybroad-band-photometrygiant-starsradial-velocitygalaxiesgalaxy-kinematicsmetallicityWe present a homogeneous kinematic analysis of red giant branch stars within 18 of the 28 Andromeda dwarf spheroidal (dSph) galaxies, obtained using the Keck I/LRIS and Keck II/DEIMOS spectrographs. Based on their g-i colors (taken with the CFHT/MegaCam imager), physical positions on the sky, and radial velocities, we assign probabilities of dSph membership to each observed star. Using this information, the velocity dispersions, central masses, and central densities of the dark matter halos are calculated for these objects, and compared with the properties of the Milky Way dSph population. We also measure the average metallicity ([Fe/H]) from the co-added spectra of member stars for each M31 dSph and find that they are consistent with the trend of decreasing [Fe/H] with luminosity observed in the Milky Way population. We find that three of our studied M31 dSphs appear as significant outliers in terms of their central velocity dispersion, And XIX, XXI, and XXV, all of which have large half-light radii (>~700pc) and low velocity dispersions ({sigma}_v_<5km/s). In addition, And XXV has a mass-to-light ratio within its half-light radius of just [M/L]_half_=10.3_-6.7_^7.0^, making it consistent with a simple stellar system with no appreciable dark matter component within its 1{sigma} uncertainties. We suggest that the structure of the dark matter halos of these outliers have been significantly altered by tides.2013ApJ...768..172Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/768/172CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/758/11 : Bayesian distances to M31 satellites (Conn+, 2012)J/ApJ/752/45 : SPLASH: Stellar spectroscopy of M31 satellites (Tollerud+, 2012)J/AJ/144/4 : Properties of dSph in the Local Group (McConnachie+, 2012)J/MNRAS/390/1437 : Stellar streams in Andromeda (M31) (Chapman+, 2008)J/MNRAS/383/183 : CaII triplet of RGB from VLT/FLAMES obs. (Battaglia+, 2008)J/MNRAS/380/281 : Faint galactic satellites spectrosc. survey (Martin+, 2007)J/MNRAS/375/831 : Draco MegaCam, INT and HST photometry (Segall+, 2007)J/AJ/124/1464 : Variable stars in Andromeda VI (Pritzl+, 2002)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/768/172https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/768/172http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/768/172https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/768/172https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/768/172http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/768/172GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/768/172/table2 (Details of spectroscopic observations)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/768/172/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/768/172/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/768/172/table2?GETtext/xml+votable180.050000true17.57587547.63147220.005555555555555556Cone search capability for table J/ApJ/768/172/table3 (Details of probable dSph members)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/768/172/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/768/172/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/768/172/table3?GETtext/xml+votable180.050000true17.509916747.63013890.005555555555555556Cone search capability for table J/ApJ/768/172/dsph (Structural properties and kinematic properties of M31 dSphs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/768/172/dsph?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/768/172/dsph?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/768/172/dsph?GETtext/xml+votable180.050000true17.5712547.6280560.0055555555555555566/2108 2110 2234 2297 2565 2572 2573 2628 2668 2746 2755 2758 2767 2781 2789 2830 2852 13505 13655 20262 20437 20440https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/768/172?format=asciiInfraredOpticaldefaultJ/ApJ/768/172/table2Details of spectroscopic observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalField (dwarf spheroidal) namemeta.id;meta.maincharm_Gal[ab] Index in case of multiple observationsmeta.code.multipcharDateObservation datetime.epoch;obsnullablen_DateObservation on several daysmeta.notecharInstInstrument and gratinginstrcharRes[1.3/3.5] Resolution in {AA}0.1nmspect.resolutionfloatRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainPA[0/315] Slit position angledegpos.posAngintExp[1200/5400] Exposure timestime.duration;obs.exposureintNtar[33/196] Number of targets observedmeta.idintNmem[1/43] Number of member stars observedmeta.numberintJ/ApJ/768/172/table3Details of probable dSph membersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalField (dwarf spheroidal) namemeta.id.parentcharm_Gal[ab] Index in case of multiple observationsmeta.code.multipcharID[1/172] Star identifier in Galmeta.id;meta.mainintRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.maingmag[21.4/25] The CFHT/MegaCam g-band magnitudemagphot.mag;em.opt.Bfloatimag[20.3/24] The CFHT/MegaCam i-band magnitudemagphot.mag;em.opt.IfloatHRV[-604.5/918.2] Heliocentric radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloate_HRV[1.2/227] Error in HRVkm/sstat.errorfloatS/N[0.3/17] Signal-to-noise (per Angstrom)stat.snrfloatPi[0/1] Likelihood of membership (1)stat.likelihoodfloatObsDetails of this observationmeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/ApJ/768/172/dsphStructural properties and kinematic properties of M31 dSphsGalDwarf galaxy namemeta.id;meta.maincharprimaryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintn_Gal[c] And XXX = Cas IImeta.notecharNoNumber of observations of this dSph (table2)meta.numberintnullableNsNumber of probable red giant members in this galaxymeta.numberintnullableRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainVMag[-10.6/-6.3] Absolute V-band magnitudemagphot.mag;em.opt.Vfloatrh[114/1481] Half-light radiuspcphys.size.radiusintE_rh[9/112] Positive uncertainty on rhpcstat.error;stat.maxinte_rh[12/271] Negative uncertainty on rhpcstat.errorintDist[650/1255] Distancekpcpos.distance;pos.heliocentricintE_Dist[21/218] Positive uncertainty on Distkpcstat.error;stat.maxinte_Dist[21/474] Negative uncertainty on Distkpcstat.errorinteta[1.5/5] Free parameter {eta} (1)stat.fit.paramfloatRV[-558/-107] Radial velocitykm/sphys.veloc;pos.heliocentricfloatE_RV[0.9/6] Positive error on RVkm/sstat.error;stat.maxfloate_RV[0.9/7] Negative error on RVkm/sstat.errorfloatsigV[0/15] Velocity dispersion {sigma}_V_km/sphys.veloc.dispersionfloatE_sigVPositive error on sigVkm/sstat.error;stat.maxfloatf_sigV[*] non-reliable sigV (2)meta.codechare_sigV[1/8.1] Negative error on sigVkm/sstat.errorfloatMh[0/8.3] Mass contained within the half-light radius1e+07solMassphys.massfloatE_Mh[0.08/5] Positive error on Mh1e+07solMassstat.error;stat.maxfloate_Mh[0.06/5] Negative error on Mh1e+07solMassstat.errorfloat[M/L][0/1391] Dynamical central mass-to-light ratiosolMass/solLumpos.parallax.dynfloatE_[M/L][4.2/1039] Positive error on [M/L]solMass/solLumstat.error;stat.maxfloate_[M/L][3.9/1128] Negative error on [M/L]solMass/solLumstat.errorfloat[Fe/H][-2.2/-1.4] Spectroscopic [Fe/H]log(Sun)phys.abund.Fefloate_[Fe/H][0.1/0.6] [Fe/H] uncertaintylog(Sun)stat.error;phys.abund.FefloatSimbadSimbad column added by the CDSmeta.ref.urlchar