J/MNRAS/429/1981ivo://CDS.VizieR/J/MNRAS/429/1981doi:10.26093/cds/vizier.74291981CDSBarentsen G.Vink J.S.Drew J.E.Sale S.E.2024-07-20T20:13:50Z2017-08-28T14:12:42ZCDS support team

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

cds-question@unistra.fropen-star-clusterspre-main-sequence-starsinfrared-photometryThere are many pertinent open issues in the area of star and planet formation. Large statistical samples of young stars across star-forming regions are needed to trigger a breakthrough in our understanding, but most optical studies are based on a wide variety of spectrographs and analysis methods, which introduces large biases. Here we show how graphical Bayesian networks can be employed to construct a hierarchical probabilistic model which allows pre-main-sequence ages, masses, accretion rates and extinctions to be estimated using two widely available photometric survey data bases (Isaac Newton Telescope Photometric H{alpha} Survey r'/H{alpha}/i' and Two Micron All Sky Survey J-band magnitudes). Because our approach does not rely on spectroscopy, it can easily be applied to homogeneously study the large number of clusters for which Gaia will yield membership lists. We explain how the analysis is carried out using the Markov chain Monte Carlo method and provide python source code. We then demonstrate its use on 587 known low-mass members of the star-forming region NGC 2264 (Cone Nebula), arriving at a median age of 3.0Myr, an accretion fraction of 20+/-2 per cent and a median accretion rate of 10-8.4M{sun}/yr. The Bayesian analysis formulated in this work delivers results which are in agreement with spectroscopic studies already in the literature, but achieves this with great efficiency by depending only on photometry. It is a significant step forward from previous photometric studies because the probabilistic approach ensures that nuisance parameters, such as extinction and distance, are fully included in the analysis with a clear picture on any degeneracies.2013MNRAS.429.1981Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/429/1981CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/321 : IPHAS DR2 Source Catalogue (Barentsen+, 2014)J/AJ/135/441 : VRIH{alpha} photometry in NGC 2264 (Sung+, 2008)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/429/1981https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/429/1981http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/429/1981https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/429/1981https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/429/1981http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/429/1981GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/429/1981/sample (IPHAS and 2MASS photometry (table 3) and posterior expectation values and standard deviations for parameters of (table 4) for known members of NGC 2264 which satisfy our selection and quality criteria)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/429/1981/sample?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/429/1981/sample?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/429/1981/sample?GETtext/xml+votable180.050000true99.98291679.71105560.0055555555555555566/23636-23637 23639 238101.1166583743361574e-19 1.7003137259100215e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/429/1981?format=asciiInfrareddefaultJ/MNRAS/429/1981/sampleIPHAS and 2MASS photometry (table 3) and posterior expectation values and standard deviations for parameters of (table 4) for known members of NGC 2264 which satisfy our selection and quality criteriaComCommentsmeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSungObject identifier (CNNNNN) as defined by Sung et al. (2008, Cat. J/AJ/135/441) (G1)meta.id;meta.maincharIPHASIPHAS name (JHHMMSS.ss+DDMMSS.s)meta.idcharrmagIPHAS r magnitudemagphot.mag;em.opt.Rfloate_rmagrms uncertainty on rmagmagstat.error;phot.mag;em.opt.RfloatHamagIPHAS H{alpha} magnitudemagphot.flux;em.line.Halphafloate_Hamagrms uncertainty on Hamagmagstat.error;phot.mag;em.IR.HfloatimagIPHAS i magnitudemagphot.mag;em.opt.Ifloate_imagrms uncertainty on imagmagstat.error;phot.mag;em.opt.IfloatJmag2MASS J magnitudemagphot.mag;em.IR.Jfloate_Jmagrms uncertainty on Jmagmagstat.error;phot.mag;em.IR.JfloatHmag2MASS H magnitudemagphot.mag;em.IR.Hfloatu_HmagUncertainty flag on Hmagmeta.code.errorchare_Hmag? rms uncertainty on Hmagmagstat.error;phot.mag;em.IR.HfloatnullableKmag2MASS K magnitudemagphot.mag;em.IR.Kfloatu_KmagUncertainty flag on Kmagmeta.code.errorchare_Kmag? rms uncertainty on Kmagmagstat.error;phot.mag;em.IR.KfloatnullableSimbadSimbad column added by the CDSmeta.ref.urlcharlogA0Extinction parameterlog(mag)phys.absorptionfloate_logA0rms uncertainty on logA0log(mag)stat.errorfloatlogMassStellar masslog(solMass)phys.massfloate_logMassrms uncertainty on logMasslog(solMass)stat.error;phys.massfloatlogAgeStellar agelog(yr)time.agefloate_logAgerms uncertainty on logAgelog(yr)stat.error;time.agefloatlogEWHaH{alpha} emission equivalent widthlog(0.1nm)spect.line.eqWidth;em.line.Halphafloate_logEWHarms uncertainty on logEWHalog(0.1nm)stat.errorfloatlogLHaExcess H{alpha} luminositylog(solLum)phys.luminosity;em.line.Halphafloate_logLHarms uncertainty on logLHalog(solLum)stat.errorfloatlogdMacc/dt? Accretion ratelog(solMass.yr**-1)arith.ratefloatnullablee_logdMacc/dt? rms uncertainty on logdMacc/dtlog(solMass.yr**-1)stat.errorfloatnullable_RAPositions from IPHAS name (right ascension part)degpos.eq.ra;meta.main_DEPositions from IPHAS name (declination part)degpos.eq.dec;meta.main