J/ApJ/831/165ivo://CDS.VizieR/J/ApJ/831/165doi:10.26093/cds/vizier.18310165CDSVivas A.K.Zinn R.Farmer J.Duffau S.Ping Y.2017-06-16T12:32:41Z2017-03-09T09:26:45ZCDS support team

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

cds-question@unistra.frvariable-starsradial-velocitysurveysstellar-distanceinfrared-photometryvisible-astronomyphotometryWe use a combination of spatial distribution and radial velocity to search for halo substructures in a sample of 412 RR Lyrae stars (RRLSs) that covers a region of ~525 square degrees of the Virgo overdensity (VOD) and spans distances from the Sun from 4 to 75kpc. With a friends-of-friends algorithm we identified six high-significance groups of RRLSs in phase space, which we associate mainly with the VOD and with the Sagittarius stream. Four other groups were also flagged as less significant overdensities. Three high-significance and three lower-significance groups have distances between ~10 and 20kpc, which places them in the distance range attributed by others to the VOD. The largest of these is the Virgo stellar stream at 19kpc, which has 18 RRLSs, a factor of two increase over the number known previously. While these VOD groups are distinct according to our selection criteria, their overlap in position and distance and, in a few cases, similarity in radial velocity are suggestive that they may not all stem from separate accretion events. Even so, the VOD appears to be caused by more than one overdensity. The Sagittarius (Sgr) stream is a very obvious feature in the background of the VOD at a mean distance of 44kpc. Two additional high-significance groups were detected at distances >40kpc. Their radial velocities and locations differ from the expected path of the Sgr debris in this part of the sky, and they are likely to be remnants of other accretion events.2016ApJ...831..165Vhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/831/165CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIII/176 : RR Lyrae Metallicities (Layden 1994)J/ApJ/816/80 : The SEGUE K giant survey. III. Galactic halo (Janesh+, 2016)J/MNRAS/446/2251 : Southern Catalina Survey type-ab RR Lyrae (Torrealba+, 2015)J/ApJ/808/11 : RR Lyrae stars in M4. II. Spitzer/IRAC phot. (Neeley+, 2015)J/ApJS/213/9 : Catalina Surveys periodic variable stars (Drake+, 2014)J/ApJ/781/22 : Region I of La Silla QUEST RR Lyrae star survey (Zinn+, 2014)J/A+A/566/A118 : A comprehensive view of Virgo stellar stream (Duffau+, 2014)J/MNRAS/441/1230 : RRLyr stars in the Catalins Sky Survey (CS2) (Abbas+, 2014)J/ApJ/776/26 : RRab stars in the Orphan stream distances (Sesar+, 2013)J/ApJ/765/154 : RR Lyrae stars in the Catalina Sky Survey (Drake+, 2013)J/ApJ/763/32 : Galactic halo RRab stars from CSS (Drake+, 2013)J/AJ/146/21 : LINEAR. II. Catalog of RR Lyrae stars (Sesar+, 2013)J/AJ/144/114 : Radial velocities of 6 field RR Lyrae (Sesar+, 2012)J/AJ/140/1337 : RV of 111 Galactic halo stars in Virgo (Brink+, 2010)J/AJ/139/59 : Milky Way halo velocity dispersion profile (Brown+, 2010)J/MNRAS/398/1757 : RR Lyraes in SDSS stripe 82 (Watkins+, 2009)J/ApJ/691/306 : Photom. of RR Lyrae candidates in Virgo stream (Prior+, 2009)J/AJ/136/1645 : Spectroscopy of bright QUEST RR Lyrae stars (Vivas+, 2008)J/AJ/132/714 : QUEST RR Lyrae survey. II. Halo overdensities (Vivas+, 2006)J/AJ/127/1158 : QUEST RR Lyrae Survey first catalog (Vivas+, 2004)http://www.sdss3.org/ : SDSS-III home pagehttp://www.lpl.arizona.edu/css/ : Catalina Sky Survey home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/831/165https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/831/165http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/831/165https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/831/165https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/831/165http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/831/165GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/831/165/table2 (Heliocentric Hbeta and Hgamma radial velocity for the RR Lyrae stars observed with the SOAR telescope)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/831/165/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/831/165/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/831/165/table2?GETtext/xml+votable180.050000true184.03608610.37388890.005555555555555556Cone search capability for table J/ApJ/831/165/table3 (Heliocentric Halpha, Hbeta and Hgamma radial velocity for the RR Lyrae stars observed with the WIYN telescope)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/831/165/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/831/165/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/831/165/table3?GETtext/xml+votable180.050000true176.037011.40570.005555555555555556Cone search capability for table J/ApJ/831/165/table1 (Heliocentric radial velocity for the RR Lyrae stars from individual SDSS DR12 spectra)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/831/165/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/831/165/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/831/165/table1?GETtext/xml+votable180.050000true175.5800417-0.15711110.005555555555555556Cone search capability for table J/ApJ/831/165/table4 (Position, light curve parameters, distance and radial velocity for the RR Lyrae stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/831/165/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/831/165/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/831/165/table4?GETtext/xml+votable180.050000true175.439548.951940.0055555555555555565/6396 6505 6509 6511 6528 6543 6546 6554 6563 6566 6569 6576 6583 6591 6595 6604 6625 6632 6/25437 25559 25563 25565 25566 25567 25575 25581 25583 25588 25590 25591 25592 25593 25596 25597 25599 25701 25716 25725 25726 25813 25821 25823 25839 25844 25846 25847 25848 25849 25851 25852 25853 25855 25896 25987 25988 25991 25993 25995 25997 25998 25999 26008 26010 26011 26016 26018 26019 26026 26029 26031 26032 26033 26034 26043 26088 26089 26094 26116 26120 26123 26124 26141 26142 26144 26145 26157 26158 26159 26162 26163 26165 26166 26167 26170 26171 26177 26178 26180 26181 26182 26188 26189 26190 26192 26194 26195 26196 26197 26199 26200 26201 26202 26205 26207 26208 26209 26211 26212 26215 26221 26222 26223 26224 26225 26227 26229 26230 26234 26235 26237 26238 26239 26241 26244 26246 26247 26251 26257 26258 26259 26261 26263 26269 26271 26272 26273 26274 26280 26282 26285 26288 26289 26299 26300 26303 26311 26313 26318 26320 26321 26322 26325 26328 26330 26331 26338 26339 26340 26341 26343 26348 26354 26355 26356 26359 26360 26362 26369 26370 26371 26374 26375 26377 26378 26379 26385 26386 26388 26389 26390 26394 26395 26402 26403 26404 26405 26407 26408 26411 26412 26413 26414 26421 26422 26425 26430 26431 26434 26435 26436 26438 26456 26458 26465 26466 26467 26468 26470 26472 26473 26498 26499 26505 26506 26509 26510 26511 26512 26513 26515 26516 26517 26522 26533 26534 26536 26537 26540 26964 26966 26970 26974 26975 26993 26996 27648 27650 27652 27654 27655 27662 27668 27671 27673 27675 27684 27692 27702 27703 27706 27711 27716 27717 27720 27723 27725 27727 27729 27731 27732 27734 27736 27738 27750 27753 27754 27783 27794 27796 27800https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/831/165?format=asciiInfraredOpticaldefaultJ/ApJ/831/165/table2Heliocentric Hbeta and Hgamma radial velocity for the RR Lyrae stars observed with the SOAR telescoperecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintPhSurvPhotometric Survey where the RR Lyrae star was catalogued (G1)meta.idcharIDID of the RR Lyrae star in the Photometric Surveymeta.id;meta.maincharHJDHeliocentric Julian Date of the spectrum at mid-exposuredtime.epochdoubleExp[900/3600] Exposure Time of the spectrumstime.duration;obs.exposureintHRV(Hb)[30/325] Heliocentric radial velocity measured at the Balmer line H{beta}km/sspect.dopplerVeloc;pos.heliocentricfloate_HRV(Hb)[10/32] Error in HRV(Hb)km/sstat.errorfloatHRV(Hg)[-23/363] Heliocentric radial velocity measured at the Balmer line H{gamma}km/sspect.dopplerVeloc;pos.heliocentricfloate_HRV(Hg)[15/43] Error in HRV(Hg)km/sstat.errorfloatSCatData from LSQ (Zinn+, 2014, J/ApJ/781/22), QUEST (Vivas+, 2004, J/AJ/127/1158), CRTS (Drake+, 2013, J/ApJS/213/9) and LINEAR (Sesar+, 2013, J/AJ/146/21) within 1"meta.ref.urlintnullableAllDisplay all data for this star in this catalogue (tables 1-4)meta.ref.urlcharSloanDisplay the online SDSS data for the nearest objectmeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/ApJ/831/165/table3Heliocentric Halpha, Hbeta and Hgamma radial velocity for the RR Lyrae stars observed with the WIYN telescoperecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintPhSurvPhotometric Survey where the RR Lyrae star was catalogued (G1)meta.idcharIDID of the RR Lyrae star in the Photometric Survey (G2)meta.id;meta.maincharHJDHeliocentric Julian Date of the spectrum at mid-exposuredtime.epochdoubleExp[900/2700] Exposure Time of the spectrumstime.duration;obs.exposureintHRV(Ha)[-201/321] Heliocentric radial velocity measured at the Balmer line H{alpha}km/sspect.dopplerVeloc;pos.heliocentricfloatHRV(Hb)[-196/326] Heliocentric radial velocity measured at the Balmer line H{beta}km/sspect.dopplerVeloc;pos.heliocentricfloatHRV(Hg)[-170/294]? Heliocentric radial velocity measured at the Balmer line H{gamma}km/sspect.dopplerVeloc;pos.heliocentricfloatnullableSCatData from LSQ (Zinn+, 2014, J/ApJ/781/22), QUEST (Vivas+, 2004, J/AJ/127/1158), CRTS (Drake+, 2013, J/ApJ/763/32 and J/ApJS/213/9) and LINEAR (Sesar+, 2013, J/AJ/146/21) within 1"meta.ref.urlintnullableAllDisplay all data for this star in this catalogue (tables 1-4)meta.ref.urlcharSloanDisplay the online SDSS data for the nearest objectmeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/ApJ/831/165/table1Heliocentric radial velocity for the RR Lyrae stars from individual SDSS DR12 spectraSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintPhSurvPhotometric Survey where the RR Lyrae star was catalogued (G1)meta.idcharIDID of the RR Lyrae star in the Photometric Survey (G2)meta.id;meta.maincharSpSurvSDSS spectroscopic survey (boss, sdss or segue1)meta.idcharHJDHeliocentric Julian Date of the spectrum at mid-exposuredtime.epochdoubleExp[900/6902] Exposure Time of the spectrumstime.duration;obs.exposurefloatHRV[-196/383] Heliocentric radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloate_HRV[1/30] Error in the heliocentric radial velocitykm/sstat.errorfloatLSQData from LSQ (Zinn+, 2014, J/ApJ/781/22) within 1"meta.ref.urlintnullableQUESTData from QUEST (Vivas+, 2004, J/AJ/127/1158 and Duffau+, 2014, J/A+A/566/A118) within 1"meta.ref.urlintnullableCRTSData from CRTS (Drake+, 2013, J/ApJ/763/32; J/ApJ/765/154; J/ApJS/213/9 and Abbas+, 2014, J/MNRAS/441/1230) within 1"meta.ref.urlintnullableLINEARData from LINEAR (Sesar+, 2013, J/AJ/146/21) within 1"meta.ref.urlintnullableSEKBOData from SEKBO (Prior+, 2009, J/ApJ/691/306) within 1"meta.ref.urlintnullableAllDisplay all data for this star in this catalogue (tables 1-4)meta.ref.urlcharSloanDisplay the online SDSS data for the nearest objectmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/ApJ/831/165/table4Position, light curve parameters, distance and radial velocity for the RR Lyrae starsSimbadNameSimbad column added by the CDSmeta.idcharGroup[1/10]? Group to which the star belongs (1)meta.idintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintPhSurvPhotometric Survey where the RR Lyrae star was catalogued (G1)meta.idcharIDID of the RR Lyrae star in the Photometric Survey (G2)meta.id;meta.maincharprimaryRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainTypeType of RR Lyrae star ("ab": 271 stars or "c": 141 stars)meta.notecharVmag[13.6/20.1] Mean magnitude in the V-bandmagphot.mag;em.opt.VfloatPer[0.2/0.9] Perioddtime.perioddoubleVAmp[0.1/1.5] Amplitude in the V-bandmagphot.mag;em.opt.VfloatDist[4/77] Distance from the Sunkpcpos.distance;pos.heliocentricfloatNsp[1/6] Number of spectra used to derive the radial velocitymeta.numberintHRV[-205/400] Heliocentric systemic radial velocitykm/sspect.dopplerVeloc;pos.heliocentricintVgsr[-292/301] Systemic velocity in the galactic standard of restkm/sphys.veloc;pos.galacticinte_Vgsr[2/42] Error in the systemic velocitykm/sstat.errorintLSQData from LSQ (Zinn+, 2014, J/ApJ/781/22) within 1"meta.ref.urlintnullableQUESTData from QUEST (Vivas+, 2004, J/AJ/127/1158 and Duffau+, 2014, J/A+A/566/A118) within 1"meta.ref.urlintnullableCRTSData from CRTS (Drake+, 2013, J/ApJ/763/32; J/ApJ/765/154; J/ApJS/213/9 and Abbas+, 2014, J/MNRAS/441/1230) within 1"meta.ref.urlintnullableLINEARData from LINEAR (Sesar+, 2013, J/AJ/146/21) within 1"meta.ref.urlintnullableSEKBOData from SEKBO (Prior+, 2009, J/ApJ/691/306) within 1"meta.ref.urlintnullableAllDisplay all data for this star in this catalogue (tables 1-4)meta.ref.urlcharSloanDisplay the online SDSS data for the nearest objectmeta.ref.urlchar