J/AJ/156/84ivo://CDS.VizieR/J/AJ/156/84doi:10.26093/cds/vizier.51560084CDSKounkel M.Covey K.Suarez G.Roman-Zuniga C.Hernandez J.Stassun K.,Jaehnig K.O.Feigelson E.D.Ramirez K.P.Roman-Lopes A.Da Rio N.,Stringfellow G.S.Kim J.S.Borissova J.Fernandez-Trincado J.G.,Burgasser A.Garcia-Hernandez D.A.Zamora O.Pan K.Nitschelm C.2020-05-04T14:24:11Z2019-02-28T12:21:13ZCDS support team

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

cds-question@unistra.frmolecular-cloudsstar-forming-regionsyoung-stellar-objectsspectroscopyradial-velocityvisible-astronomytrigonometric-parallaxproper-motionsstellar-agesstellar-radiisurveysWe present an analysis of spectroscopic and astrometric data from APOGEE-2 and Gaia DR2 (Cat. I/345) to identify structures toward the Orion Complex. By applying a hierarchical clustering algorithm to the six-dimensional stellar data, we identify spatially and/or kinematically distinct groups of young stellar objects with ages ranging from 1 to 12 Myr. We also investigate the star-forming history within the Orion Complex and identify peculiar subclusters. With this method we reconstruct the older populations in the regions that are currently largely devoid of molecular gas, such as Orion C (which includes the {sigma} Ori cluster) and Orion D (the population that traces Ori OB1a, OB1b, and Orion X). We report on the distances, kinematics, and ages of the groups within the Complex. The Orion D group is in the process of expanding. On the other hand, Orion B is still in the process of contraction. In {lambda} Ori the proper motions are consistent with a radial expansion due to an explosion from a supernova; the traceback age from the expansion exceeds the age of the youngest stars formed near the outer edges of the region, and their formation would have been triggered when they were halfway from the cluster center to their current positions. We also present a comparison between the parallax and proper-motion solutions obtained by Gaia DR2 and those obtained toward star-forming regions by the Very Long Baseline Array.2018AJ....156...84Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/156/84CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)I/345 : Gaia DR2 (Gaia Collaboration, 2018)J/AJ/121/2124 : {lambda} Ori pre-main-sequence stars photometryJ/AJ/123/387 : VRI photometry of {lambda} Ori star-forming regionJ/AJ/129/907 : New Ori OB1 members (Briceno+, 2005)J/ApJ/661/1119 : Spectroscopy in the 25 Ori group (Briceno+, 2007)J/A+A/485/931 : Young stars and brown dwarfs in Ori OB1b (Caballero+, 2008)J/A+A/488/167 : Low-mass stars in {sigma} Ori and {lambda} OriJ/ApJ/676/1109 : Velocities of stars in the Orion Nebula ClusterJ/MNRAS/385/2210 : Spectroscopy around lam Ori and sig Ori (Maxted+, 2008)J/ApJ/697/1103 : Kinematics of Orion Nebula Cluster (Tobin+, 2009)J/ApJ/722/1092 : Optical photometry of the ONC. II. (Da Rio+, 2010)J/ApJ/722/1226 : IR photometry in {lambda} Orionis cluster (Hernandez+, 2010)J/AJ/144/192 : Spitzer survey of Orion A and B. I. YSO catalogJ/ApJ/754/30 : VISTA IR photometry of {sigma} Ori clusterJ/ApJ/764/114 : BVRI photometry of stars in Orion A (Hsu+, 2013)J/ApJ/768/99 : X-ray survey of YSOs in Orion A (Pillitteri+, 2013)J/A+A/564/A29 : Optical and near-infrared photometry in Orion AJ/ApJ/782/8 : Spectroscopy of 104 objects in the ONC (Ingraham+, 2014)J/ApJ/794/36 : {sigma} Orionis cluster stellar populationJ/MNRAS/444/1793 : 25 Ori group low-mass stars (Downes+, 2014)J/ApJ/818/59 : IN-SYNC. IV. YSOs in Orion A (Da Rio+, 2016)J/A+A/608/A148 : Stellar populations towards Orion with Gaia DR1J/AJ/153/188 : Spectroscopy of the foreground population in Orion AJ/AJ/154/14 : Low-mass stars in 25 Ori group and Orion OB1aJ/ApJ/844/138 : Optical spectroscopy toward Orion B fields (Kounkel+, 2017)J/A+A/610/A12 : Clustering the Orion B giant molecular cloud (Bron+, 2018)J/A+A/619/A106 : 3D shape of Orion A from Gaia DR2 (Grossschedl+, 2018)J/ApJS/236/27 : APOGEE-2 survey of Orion Complex (OSFC). I. (Cottle+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/156/84https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/156/84http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/156/84https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/156/84https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/156/84http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/156/84GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/156/84/table1 (Properties derived from the APOGEE spectra towards the stars in Orion)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/156/84/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/156/84/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/156/84/table1?GETtext/xml+votable180.050000true85.13871002197271-10.1480636596680.005555555555555556Cone search capability for table J/AJ/156/84/table2 (Astrometric solutions from Gaia utilized in the analysis)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/156/84/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/156/84/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/156/84/table2?GETtext/xml+votable180.050000true78.993744196366-10.99169853511730.005555555555555556Cone search capability for table J/AJ/156/84/table3 (Identified groups and their properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/156/84/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/156/84/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/156/84/table3?GETtext/xml+votable180.050000true83.70438251039-6.7550982072531780.0055555555555555563/357 370 4/1337 1339 1342 1424 1425 1427 1436 1437 1439 1474 1504 5/5311 5347 5353 5354 5355 5362 5374 5653 5655 5704 5705 5707 5732 5733 5735 5752 5753 5755 5844 5845 5847 5890 5902 5938 5944 5945 5946 6020 6021 6022 6024 6025 6/21239 21243 21310 21311 21387 21409 21410 21411 21440 21442 21443 21452 21454 21455 21488 21490 21491 21500 21502 21503 22609 22610 22611 22616 22617 22619 22644 22645 22647 22825 22917 22937 22965 22967 23016 23017 23019 23365 23384 23385 23412 23413 23552 23554 23555 23564 23566 23567 23600 23602 23603 23612 23614 23615 23744 23746 23747 23756 23758 23759 23788 23792 24092 24105 24108 24112 24128https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/156/84?format=asciiOpticaldefaultJ/AJ/156/84/table1Properties derived from the APOGEE spectra towards the stars in OrionSimbadNameSimbad column added by the CDSmeta.idcharGaia? Gaia DR2 identifiermeta.idnullableprimaryNep[1/27] Number of epochsmeta.numberintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.main2MASS2MASS position based identifier (2MHHMMSSss+DDMMSSs)meta.id;meta.maincharmoreindicates data in Table 2 for this starmeta.ref.urlcharTeff[2300.05/14999.8] Effective temperatureKphys.temperature.effectivedoublee_Teff[1.14962/109706] Uncertainty in TeffKstat.error;phys.temperature.effectivedoublelogg[-0.497235/5.99984] Surface gravitylog(cm.s**-2)phys.gravitydoublee_logg[0.0061962/3.78714] Uncertainty in logglog(cm.s**-2)stat.errordoublel_RVmean[<] Limit flag on RVmeanmeta.code.errorcharRVmean[-170.587/552.16] Mean radial velocitykm/sspect.dopplerVeloc;stat.meandoublee_RVmean[0.0658911/0.999541]? Uncertainty in RVmeankm/sstat.errordoublenullableFbol[0.028791/2481.34]? Bolometric flux (in 10^-10^ erg/s/cm^2^)1e-13W.m**-2phot.flux.boldoublenullablee_Fbol[0/272.365]? Uncertainty in Fbol (in 10^-10^ erg/s/cm^2^)1e-13W.m**-2stat.errordoublenullableAv[0.05/4.5]? Visual extinctionmagphys.absorption;em.opt.Vfloatnullablee_Av[0/4.5]? Uncertainty in Avmagstat.errordoublenullableTheta[4.91477/166.521]? Stellar angular radius {Theta}uarcsecphys.angSize;srcdoublenullablee_Theta[0.055472/534.068]? Uncertainty in Thetauarcsecstat.error;pos.posAngdoublenullableFlag[-1/2]? Flag (1)meta.code.errorintnullableGroupStellar group in Orion (see Table 3)meta.id.parentcharJ/AJ/156/84/table2Astrometric solutions from Gaia utilized in the analysisGaiaGaia DR2 identifiermeta.id;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainindexedDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainindexedPlx[-0.280675/25.0894] Gaia DR2 parallaxmaspos.parallaxdoublee_Plx[0.0179231/0.0999935] Uncertainty in Plxmasstat.error;pos.parallaxdoublepmRA[-116.218/357.827] Gaia DR2 proper motion, in Right Ascension (pmRA*cosDE)mas/yrpos.pm;pos.eq.radoublee_pmRA[0.028026/0.199834] Uncertainty in pmRAmas/yrstat.error;pos.pm;pos.eq.radoublepmDE[-383.421/87.8759] Gaia DR2 proper motion, in Declinationmas/yrpos.pm;pos.eq.decdoublee_pmDE[0.0260162/0.199260] Uncertainty in pmDEmas/yrstat.error;pos.pm;pos.eq.decdoubleGroupStellar group in Orion (see Table 3)meta.id.parentcharJ/AJ/156/84/table3Identified groups and their propertiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGroupStellar group in Orionmeta.id.parentcharRAJ2000Mean group Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.maine_RAJ20001{sigma} dispersion about mean for RAdegdegstat.error;pos.eq.radoubleDEJ2000Mean group Declination in decimal degrees (J2000)degpos.eq.dec;meta.maine_DEJ20001{sigma} dispersion about mean for DEdegdegstat.error;pos.eq.decdoubleVR[-0.855298/15.4463]? Mean group space velocity in radial direction relative to LSRkm/spos.dirCos;stat.meandoublenullablee_VR[0.0858054/4.34537]? 1{sigma} dispersion about mean for VRkm/sstat.errordoublenullableVRA[-3.38991/2.69296] Mean group space velocity, in RA relative to LSRmas/yrphys.velocdoublee_VRA[0.0509354/1.21063]? 1{sigma} dispersion about mean for VRAmas/yrstat.errordoublenullableVDE[0.378125/5.53187] Mean group space velocity, in DE relative to LSRmas/yrphys.velocdoublee_VDE[0.0378445/1.1808]? 1{sigma} dispersion about mean for VDEmas/yrstat.errordoublenullableHRV[15.8466/37.6226]? Mean group space velocity in radial direction relative to heliocenterkm/spos.dirCos;stat.meanfloatnullablepmRA[-3.23894/2.77745] Mean group space velocity, proper motion in RAmas/yrpos.pm;pos.eq.radoublepmDE[-3.73049/2.14493] Mean group space velocity, proper motion in DEmas/yrpos.pm;pos.eq.decdoublePlx[2.1517/3.5666] Mean group parallaxmaspos.parallax;stat.meandoublee_Plx[0.0295239/0.214648]? 1{sigma} dispersion about mean for Plxmasstat.error;pos.parallaxdoublenullableAge-CMD[0.501/18.2]? Mean group age, Color-Magnitude diagramMyrtime.age;stat.meandoublenullablee_Age-CMD[0.534367/5.09486]? 1{sigma} dispersion about mean for Age-CMDMyrstat.errordoublenullableAge-HR[0.35345/15.07]? Mean group age, HR diagramMyrtime.age;stat.meandoublenullablee_Age-HR[0.355818/6.65807]? 1{sigma} dispersion about mean for Age-HRMyrstat.errordoublenullableNstars[10/297] Number of stars in Groupmeta.numberintNAPOGEE[0/136]? Group members with APOGEE spectrameta.numberintnullable