J/AJ/119/3026ivo://CDS.VizieR/J/AJ/119/3026doi:10.26093/cds/vizier.51193026CDSRebull L.M.Hillenbrand L.A.Strom S.E.Duncan D.K.Patten B.M.,Pavlovsky C.M.Makidon R.Adams M.T.2023-04-06T16:50:38Z2000-10-13T21:05:45ZCDS support team

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

cds-question@unistra.frpre-main-sequence-starsvisible-astronomykron-cousins-photometrybroad-band-photometryWe present an optical study of four 45'x45' fields centered ~0.5{deg} east, west, north, and south of the Orion Nebula Cluster center. We have measured V and I_C_ photometry for ~5000 stars, and U photometry for ~1600 of these. We have obtained spectral classifications for ~300 of the stars with UVI_C_ photometry plus an additional ~200 stars located outside the area of our photometric survey. Dereddened photometry allows us to investigate the evidence for circumstellar accretion disks from excess emission at ultraviolet wavelengths, as well as the mass and age distributions of our sample. We find ~230 active accretion disk candidates and estimate the accretion disk fraction at >~40%. We use the magnitude of the ultraviolet excess to infer disk accretion rates. The mass accretion rate (dM/dt) decreases slowly with age over the limited age range spanned by our data, 1-3Myr, and increases slowly with mass over the limited mass range 0.2-1.2 M_{sun}_.2000AJ....119.3026Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/119/3026CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/113/1733 : Orion Nebula Cluster population (Hillenbrand 1997)J/AJ/116/1816 : JHKLMNOPQ photometry in Orion cluster (Hillenbrand+, 1998)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/119/3026https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/119/3026http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/119/3026https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/119/3026https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/119/3026http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/119/3026GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/119/3026/table1 (Observations I: stars in the Orion locus)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/119/3026/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/119/3026/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/119/3026/table1?GETtext/xml+votable180.050000true82.8525-5.4450.005555555555555556Cone search capability for table J/AJ/119/3026/table2 (Observations II: Apparent field stars with spectra)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/119/3026/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/119/3026/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/119/3026/table2?GETtext/xml+votable180.050000true82.87375-5.5246110.005555555555555556Cone search capability for table J/AJ/119/3026/table3 (Observations III: stars with spectroscopy only)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/119/3026/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/119/3026/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/119/3026/table3?GETtext/xml+votable180.050000true82.885417-5.2972560.0055555555555555565/5359 6/22804-22805 22848https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/119/3026?format=asciiOpticaldefaultJ/AJ/119/3026/table1Observations I: stars in the Orion locusrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintT[1,2] Table numbermeta.id;meta.datasetint[RHS2000]Sequential number (1)meta.idintFieldField numberobs.fieldintRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainIcmagCousins I magnitudemagphot.mag;em.opt.Ifloate_Icmagrms uncertainty on Icmagmagstat.errorfloatV-IcV-I_C_ colour indexmagphot.color;em.opt.V;em.opt.Ifloate_V-Icrms uncertainty on V-Icmagstat.errorfloatU-V? U-V colour indexmagphot.color;em.opt.U;em.opt.Vfloatnullablee_U-V? rms uncertainty on U-Vmagstat.errorfloatnullableSpTypeSpectral typesrc.spTypecharAImag? Extinction in I_C_ bandmagphys.absorptionfloatnullableAVmag? Extinction in V bandmagphys.absorptionfloatnullableJ/AJ/119/3026/table2Observations II: Apparent field stars with spectrarecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintT[1,2] Table numbermeta.id;meta.datasetint[RHS2000]Sequential number (1)meta.idintFieldField numberobs.fieldintRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainIcmagCousins I magnitudemagphot.mag;em.opt.Ifloate_Icmagrms uncertainty on Icmagmagstat.errorfloatV-IcV-I_C_ colour indexmagphot.color;em.opt.V;em.opt.Ifloate_V-Icrms uncertainty on V-Icmagstat.errorfloatU-V? U-V colour indexmagphot.color;em.opt.U;em.opt.Vfloatnullablee_U-V? rms uncertainty on U-Vmagstat.errorfloatnullableSpTypeSpectral typesrc.spTypecharAImag? Extinction in I_C_ bandmagphys.absorptionfloatnullableAVmag? Extinction in V bandmagphys.absorptionfloatnullableJ/AJ/119/3026/table3Observations III: stars with spectroscopy onlyFieldField numberobs.fieldintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintT[3] Table numbermeta.id;meta.datasetint[RHS2000]Sequential number ([RHS2000] 3-NNNN in Simbad)meta.idintRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainSpTypeSpectral typesrc.spTypechar