J/ApJ/722/1092ivo://CDS.VizieR/J/ApJ/722/1092doi:10.26093/cds/vizier.17221092CDSDa Rio N.Robberto M.Soderblom D.R.Panagia N.Hillenbrand L.A.,Palla F.Stassun K.G.2018-01-08T06:38:10Z2012-08-09T09:19:54ZCDS support team

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

cds-question@unistra.frhertzsprung-russell-diagramextinctionstellar-massesstellar-agesopen-star-clusterspre-main-sequence-starsstellar-spectral-typesWe present a new analysis of the stellar population of the Orion Nebula Cluster (ONC) based on multi-band optical photometry and spectroscopy. We study the color-color diagrams in BVI, plus a narrowband filter centered at 6200{AA}, finding evidence that intrinsic color scales valid for main-sequence dwarfs are incompatible with the ONC in the M spectral-type range, while a better agreement is found employing intrinsic colors derived from synthetic photometry, constraining the surface gravity value as predicted by a pre-main-sequence isochrone. We refine these model colors even further, empirically, by comparison with a selected sample of ONC stars with no accretion and no extinction. We consider the stars with known spectral types from the literature, and extend this sample with the addition of 65 newly classified stars from slit spectroscopy and 182 M-type from narrowband photometry; in this way, we isolate a sample of about 1000 stars with known spectral type. We introduce a new method to self-consistently derive the stellar reddening and the optical excess due to accretion from the location of each star in the BVI color-color diagram. This enables us to accurately determine the extinction of the ONC members, together with an estimate of their accretion luminosities. We adopt a lower distance for the Orion Nebula than previously assumed, based on recent parallax measurements. With a careful choice of also the spectral-type-temperature transformation, we produce the new Hertzsprung-Russell diagram of the ONC population, more populated than previous works.2010ApJ...722.1092Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/722/1092CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/534/A10 : HST/NICMOS III imaging in ONC (Andersen+, 2011)J/A+A/515/A13 : Very low mass objects in ONC (Rodriguez-Ledesma+, 2010)J/ApJS/183/261 : Optical photometry of the ONC (Da Rio+, 2009)J/AJ/113/1733 : Orion Nebula Cluster population (Hillenbrand 1997)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/722/1092https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/722/1092http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/722/1092https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/722/1092https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/722/1092http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/722/1092GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/722/1092/table3 (Positions in the H-R diagram and values of mass and age from Siess (2000A&A...358..593S) and Palla & Stahler (1999ApJ...525..772P))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/722/1092/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/722/1092/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/722/1092/table3?GETtext/xml+votable180.050000true83.9459167-5.29914170.0055555555555555566/21438 21439 22804 22805https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/722/1092?format=asciiOpticaldefaultJ/ApJ/722/1092/table3Positions in the H-R diagram and values of mass and age from Siess (2000A&A...358..593S) and Palla & Stahler (1999ApJ...525..772P)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[1/1753] Index number (<[DRS2009] NNNN> in Simbad)meta.id;meta.mainintRAJ2000[5] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[5] Degree of Declination (J2000)pos.eq.dec;meta.mainlogTLog of the effective temperaturelog(K)phys.temperature.effectivefloatlogL? Log of the luminositylog(solLum)phys.luminosityfloatnullableAV[0/12.15] V band extinctionmagphys.absorption;em.opt.Vfloatl_logAcLimit flag on logRmeta.code.errorcharlogAc[-5/0] Log of the accretion to total luminositiesphys.luminosity;arith.ratiofloatM.S0? Siess (S0; 2000A&A...358..593S) derived masssolMassphys.massfloatnullablelogA0? Log of the S0 derived agelog(yr)time.agefloatnullableM.P9? Palla & Stahler (P9; 1999ApJ...525..772P) derived masssolMassphys.massfloatnullablelogA9? Log of the P9 derived agelog(yr)time.agefloatnullableH97[1-9280]? Hillenbrand 1997 (Cat. J/AJ/113/1733) number (<[H97b] NNNN> in Simbad)meta.id.crossintnullableMm[0/99]? H97 membership probability%statintnullabler_SpTSpectral type reference (1)meta.ref;pos.framecharSpTMK spectral type informationsrc.spTypecharSimbadSimbad column added by the CDSmeta.refchar