J/AJ/153/188ivo://CDS.VizieR/J/AJ/153/188doi:10.26093/cds/vizier.51530188CDSFang M.Kim J.S.Pascucci I.Apai D.Zhang L.Sicilia-Aguilar A.,Alonso-Martinez M.Eiroa C.Wang H.2019-08-20T06:51:16Z2018-05-14T09:42:49ZCDS support team

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

cds-question@unistra.frstellar-associationsyoung-stellar-objectsaccretionspectroscopystellar-spectral-typesline-intensitiesextinctionstellar-massesstellar-agesWe perform a spectroscopic survey of the foreground population in Orion A with MMT/Hectospec. We use these data, along with archival spectroscopic data and photometric data, to derive spectral types, extinction values, and masses for 691 stars. Using the Spitzer Space Telescope data, we characterize the disk properties of these sources. We identify 37 new transition disk (TD) objects, 1 globally depleted disk candidate, and 7 probable young debris disks. We discover an object with a mass of less than 0.018-0.030 M_{sun}_, which harbors a flaring disk. Using the H{alpha} emission line, we characterize the accretion activity of the sources with disks, and confirm that the fraction of accreting TDs is lower than that of optically thick disks (46%+/-7% versus 73%+/-9%, respectively). Using kinematic data from the Sloan Digital Sky Survey and APOGEE INfrared Spectroscopy of the Young Nebulous Clusters program (IN-SYNC), we confirm that the foreground population shows similar kinematics to their local molecular clouds and other young stars in the same regions. Using the isochronal ages, we find that the foreground population has a median age of around 1-2 Myr, which is similar to that of other young stars in Orion A. Therefore, our results argue against the presence of a large and old foreground cluster in front of Orion A.2017AJ....153..188Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/153/188CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+AS/123/329 : New weak-line T Tauri stars in Lupus (Krautter+ 1997)J/ApJ/602/816 : Chamaeleon I star-forming region census (Luhman, 2004)J/AJ/130/1733 : Optical spectroscopy of {rho} Oph stars (Wilking+, 2005)J/A+A/460/695 : Search for Associations Containing Young stars (Torres+, 2006)J/AJ/132/866 : New M dwarfs in solar neighborhood (Riaz+, 2006)J/AJ/133/2524 : Spectra of young nearby stars (White+, 2007)J/ApJ/667/308 : Weak-line T Tauri in Spitzer c2d Survey. II. (Cieza+, 2007)J/A+A/480/735 : Young local stellar associations (Fernandez+, 2008)J/A+A/488/167 : Low-mass stars in {sigma} Ori and {lambda} Ori (Sacco+, 2008)J/A+A/500/1045 : Cool stars and brown dwarfs in Lupus clouds (Comeron+, 2009)J/A+A/504/461 : YSOs in L1630N and L1641 (Fang+, 2009)J/ApJ/691/672 : Spectrocopy of YSOs in Serpens molecular cloudJ/ApJ/712/925 : Transition circumstellar disks in Ophiuchus (Cieza+, 2010)J/ApJ/724/835 : The Spitzer c2d survey of WTTSs. III. (Wahhaj+, 2010)J/A+A/548/A56 : X-shooter spectra of 12 young stellar objectsJ/AJ/144/192 : Spitzer survey of Orion A and B. I. YSO catalogJ/ApJ/745/119 : Close companions to young stars. I. ChaI & TauJ/ApJ/749/79 : Transition disks. II. Southern MoC (Romero+, 2012)J/A+A/551/A107 : X-shooter spectra of 24 young stellar objects (Manara+, 2013)J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)J/A+A/561/A2 : 36 accreting YSOs emission lines (Alcala+, 2014)J/A+A/602/A33 : X-Shooter spectroscopy of YSOs in Lupus (Frasca+, 2017)J/A+A/605/A86 : Pre-main sequence stars VLT/X-Shooter spectra (Manara+, 2017)J/AJ/154/29 : Observation of 148 young stars toward NGC 1980https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/153/188https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/153/188http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/153/188https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/153/188https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/153/188http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/153/188GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/153/188/table4 (The parameters for young stars with X-Shooter spectra)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/153/188/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/153/188/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/153/188/table4?GETtext/xml+votable180.050000true129.23433333-78.946027780.005555555555555556Cone search capability for table J/AJ/153/188/table6 (Stellar properties for the YSOs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/153/188/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/153/188/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/153/188/table6?GETtext/xml+votable180.050000true82.9624167-7.00158330.0055555555555555565/5359 6/1029 1539 21433 21435 22804 22805 22807 22848 22850 22851 22854 24580 24608 24716 24740 24763 28746 30363 36956 36957 37012 37013 37128 38054 38191 38347 38363 38382 38687 38742 38800 42611 42614 42705 42714 42736 42885 42981 42982 42983 43545 43575 43704 47826 47828 47845https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/153/188?format=asciidefaultJ/AJ/153/188/table4The parameters for young stars with X-Shooter spectrarecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/85] Running number identifiermeta.id;meta.mainintNameStar Namemeta.idcharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainSpT-LitLiterature spectral type(s)src.spTypecharr_SpT-LitReference(s) for SpT-Litmeta.ref;pos.framecharSpTAdopted spectral typesrc.spTypecharr_SpTReference for SpTmeta.ref;pos.framecharEW(Ha)[-222.5/1.3] H{alpha} equivalent width ({AA})0.1nmspect.line.eqWidth;em.line.Halphafloatl_Lacc/L*[<] Limit flag on Lacc/L*meta.code.errorcharLacc/L*[0.003/0.096]? Accretion to stellar luminosity ratiophys.luminosity;arith.ratiofloatnullableAcc[Y/N] Accreting? (Y=Yes, N=No)meta.codecharAv[0/6.2] Line of sight extinctionmagphys.absorption;spect.linefloatRef[14/43]? Reference for accretion luminositymeta.ref;pos.frameintnullableSimbadNameSimbad column added by the CDSmeta.idcharJ/AJ/153/188/table6Stellar properties for the YSOsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/691] Running number identifiermeta.id;meta.mainintRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainSpTMK spectral type (1)src.spTypecharLum[0.019/1.039] LuminositysolLumphys.luminosityfloatAv[0/2.8] Visual extinctionmagphys.absorption;em.opt.VfloatMass[0.018/0.67] Stellar masssolMassphys.massfloatl_Age[<] Limit flag on Agemeta.code.error;time.agecharAge[0.5/22.9] Stellar ageMyrtime.agefloatf_Age[?] Uncertainty flag on Agemeta.codecharEW-Li1[0.07/1.2]? First Li 6708{AA} equivalent width ({AA})0.1nmspect.line.eqWidthfloatnullableEW-Li2[0.12/0.62]? Second Li 6708{AA} equivalent width ({AA})0.1nmspect.line.eqWidthfloatnullableEW-Ha[-249.8/0]? H{alpha} equivalent width ({AA})0.1nmspect.line.eqWidth;em.line.Halphafloatnullablealpha1[-3.12/0.32]? SED slope in spectral range 3.6-8{mu}marith.grad;instr.bandwidthfloatnullablealpha2[-2.46/0.13]? SED slope in spectral range 3.6-24{mu}marith.grad;instr.bandwidthfloatnullableTTS[CW] T Tauri type (2)src.classcharDiskDisk population (3)src.classcharCritSample selection criterion (4)meta.idcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/AJ/153/188/refsReferencesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRef[1/43] Reference numbermeta.id;meta.mainintBibCodeBibCodemeta.bib.bibcodecharAutAuthor's namemeta.bib.authorcharComCommentsmeta.notechar