J/ApJ/854/47ivo://CDS.VizieR/J/ApJ/854/47doi:10.26093/cds/vizier.18540047CDSSheffield A.A.Price-Whelan A.M.Tzanidakis A.Johnston K.V.,Laporte C.F.P.Sesar B.2019-01-09T08:07:24Z2018-12-18T15:30:21ZCDS support team

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

cds-question@unistra.frstellar-associationsvariable-starsradial-velocitystellar-distancevisible-astronomyThe Monoceros Ring (also known as the Galactic Anticenter Stellar Structure) and A13 are stellar overdensities at estimated heliocentric distances of d~11kpc and 15kpc observed at low Galactic latitudes toward the anticenter of our Galaxy. While these overdensities were initially thought to be remnants of a tidally disrupted satellite galaxy, an alternate scenario is that they are composed of stars from the Milky Way (MW) disk kicked out to their current location due to interactions between a satellite galaxy and the disk. To test this scenario, we study the stellar populations of the Monoceros Ring and A13 by measuring the number of RR Lyrae and M giant stars associated with these overdensities. We obtain low-resolution spectroscopy for RR Lyrae stars in the two structures and measure radial velocities to compare with previously measured velocities for M giant stars in the regions of the Monoceros Ring and A13, to assess the fraction of RR Lyrae to M giant stars (f_RR:MG_) in A13 and Mon/GASS. We perform velocity modeling on 153 RR Lyrae stars (116 in the Monoceros Ring and 37 in A13) and find that both structures have very low f_RR:MG_. The results support a scenario in which stars in A13 and Mon/GASS formed in the MW disk. We discuss a possible association between Mon/GASS, A13, and the Triangulum-Andromeda overdensity based on their similar velocity distributions and f_RR:MG_.2018ApJ...854...47Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/854/47CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/317 : The PPMXL Catalog (Roeser+ 2010)J/AJ/128/1177 : Galactic stellar abundances (Venn+, 2004)J/A+A/442/1127 : Library of 2500-10500{AA} synthetic spectra (Munari+, 2005)J/ApJ/708/717 : Light curve templates of RR Lyrae stars (Sesar+, 2010)J/ApJ/736/146 : Radial velocities of stars in Bootes I (Koposov+, 2011)J/ApJ/731/4 : Galactic halo as seen by the CFHTLS (Sesar+, 2011)J/AJ/144/114 : Radial velocities of 6 field RR Lyrae (Sesar+, 2012)J/ApJ/763/32 : Galactic halo RRab stars from CSS (Drake+, 2013)J/ApJ/776/26 : RRab stars in the Orphan stream distances (Sesar+, 2013)J/ApJ/793/62 : Triangulum-Andromeda stellar properties (Sheffield+, 2014)J/ApJ/844/L4 : PS1 RRab for tracing outer Virgo overdensity (Sesar+, 2017)J/AJ/153/204 : RR Lyrae stars from the PS1 3{pi} survey (Sesar+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/854/47https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/854/47http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/854/47https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/854/47https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/854/47http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/854/47GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/854/47/table1 (Properties of RR Lyrae stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/854/47/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/854/47/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/854/47/table1?GETtext/xml+votable180.050000true105.5566179964.204723480.0055555555555555566/4107 4128 4137 4138 4242 4259 4281 4289 4290 4335 4347 4634 4638 4656 4657 4674 4691 4708 4709 4736 4743 4764 4771 4816 4831 4837 4844 4850 4852 4994 5000 5002 5032 5051 6170 6172 6181 6189 6193 6198 6207 6220 6225 6230 6265 6294 6332 6343 6354 6356 6372 6391 6404 6408 6415 6443 6462 6486 6509 6530 6534 6546 6547 6556 6598 6607 6627 6628 6637 6640 6648 6651 6652 6654 6707 6730 6739 6746 6765 6772 6778 6848 6918 6920 6931 6941 6983 6989 6996 6999 7000 7017 7034 7051 7054 7060 7089 7113 7114 7115 7116 7131 7202 7203 7225 7230 7298 7302 7308 7362 7692 7707 7716 7721 7815 21816 21955 21957 21967 22343 22359 22360 22364 26670 27143 27145 27146 27176 27180 27290 27301 27303 27314 27321 40398 40442 40796 40817 40819 40914 40919 40930 40940 40943 40959https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/854/47?format=asciiOpticaldefaultJ/ApJ/854/47/table1Properties of RR Lyrae starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[DCD2013]CSS identifier (JHHMMSS.s+DDMMSS) (1)meta.id;meta.maincharGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.latDist[7/19.5] Heliocentric distancekpcpos.distancefloatHRV[-365/353] Heliocentric radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloatVGSR[-399/252] Galactic standard of rest radial velocitykm/sspect.dopplerVeloc;pos.galacticfloate_VGSR[11/24] Uncertainty in VGSRkm/sstat.errorfloatPhase[0.07/0.8] Observed phasetime.phasefloatRegStellar overdensity name (A13 or Mon/GASS)meta.id.assoccharSimbadSimbad column added by the CDSmeta.ref.urlchar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decnullableindexed