J/ApJ/906/23ivo://CDS.VizieR/J/ApJ/906/23doi:10.26093/cds/vizier.19060023CDSForbrich J.Dzib S.A.Reid M.J.Menten K.M.2022-10-14T13:03:50Z2022-06-08T07:36:16ZCDS support team

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

cds-question@unistra.fropen-star-clustersradio-sourcesradio-astronomyastrometryWe present first results of a four-epoch VLBA survey for nonthermal emission toward all 556 compact radio sources previously identified in a deep VLA survey of the Orion Nebula Cluster (ONC). We identify VLBA counterparts toward an unprecedented 123 sources. Of these, 41 do not have X-ray counterparts, of which 34 also do not display near-infrared counterparts. Since these cannot be explained by extragalactic background sources, this suggests a component of the ONC population of young stellar objects that are too deeply embedded for even X-rays to be detectable. We find pervasive variability and detect even most of the highest-S/N sources in only one out of four epochs. Neither a negative spectral index nor extreme variability in the VLA data is a good predictor of a VLBA detection.2021ApJ...906...23Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/906/23CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/405/498 : Counts and spectral indices at 8.44GHz (Windhorst+, 1993)J/ApJS/160/353 : Membership of the Orion nebula population (Getman+, 2005)J/ApJS/160/319 : COUP; observations and source lists (Getman+, 2005)J/ApJ/677/401 : Xray properties of protostars in ONC (Prisinzano+, 2008)J/AJ/146/85 : Spectral types 1576 optical stars in ONC (Hillenbrand+, 2013)J/A+A/551/A97 : Lockman Hole/XMM VLBI observations (Middelberg+, 2013)J/ApJ/822/93 : Population of compact radio sources in ONC (Forbrich+, 2016)J/A+A/587/A153 : VISION I. VISTA Orion A Survey (Meingast+, 2016)J/A+A/607/A132 : VLBA observations of the COSMOS field (Herrera Ruiz+, 2017)J/ApJ/834/142 : Gould's Belt Distances Survey. II. OMC (Kounkel+, 2017)J/ApJ/906/24 : A VLBA Survey of Radio Stars in the ONC. II. (Dzib+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/906/23https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/906/23http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/906/23https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/906/23https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/906/23http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/906/23GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/906/23/table2 (List of VLBA detections in the Orion Nebula Cluster)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/906/23/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/906/23/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/906/23/table2?GETtext/xml+votable180.050000true83.7332186-5.38695610.0055555555555555566/21439https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/906/23?format=asciiRadiodefaultJ/ApJ/906/23/table2List of VLBA detections in the Orion Nebula ClusterSimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[FRM2016]Identifiermeta.id;meta.mainintf_[FRM2016]Sources flagged only fulfill the selection criterion in the concatenated epoch BF123ABmeta.codecharCOUP[107/1473]? COUP identifier of the sourcemeta.idintnullableVISIONVISION NIR (1)meta.idcharNS/N[0/4] Number of S/N>6.5meta.numberintS/N[6.5/215] Maximum S/Nstat.snr;stat.maxfloatEpochEpoch of S/N (2)time.epochcharSep[5/663]? Separation between detection and nominal VLA positionmaspos.angDistanceintnullableNoteAdditional note or comment (3)meta.notechar_RAPosition from SIMBAD (right ascension part)degpos.eq.ra;meta.main_DEPosition from SIMBAD (declination part)degpos.eq.dec;meta.main