J/A+A/640/A128ivo://CDS.VizieR/J/A+A/640/A128doi:10.26093/cds/vizier.36400128CDSRoquette J.Alencar S.H.P.Bouvier J.Guarcello M.G.Reipurth B.2021-01-25T08:59:57Z2020-08-28T07:39:35ZCDS support team

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

cds-question@unistra.fryoung-stellar-objectsvariable-starspre-main-sequence-starslate-type-starsinfrared-photometryccd-photometryWe present the results of a J, H, and K photometric variability survey of the central 0.78 square degrees of the young OB association Cygnus OB2. We used data observed with the Wide-Field CAMera at the United Kingdom Infrared Telescope in 2007 (spanning 217 days) to investigate the light curves of 5083 low mass candidate members in the association and explore the occurrence and main characteristics of their near-infrared variability. We identified 2529 stars (~50% of the sample) with significant variability with time-scales ranging from days to months. We classified the variable stars into the following three groups according to their light curve morphology: periodic variability (1697 stars), occultation variability (124 stars), and other types of variability (726 stars). We verified that the disk-bearing stars in our sample are significantly more variable in the near-infrared than diskless stars, with a steep increase in the disk-fraction among stars with higher variability amplitude. We investigated the trajectories described by variable stars in the color-space and measured slopes for 335 stars describing linear trajectories. Based on the trajectories in the color-space, we inferred that the sample analyzed is composed of a mix of young stars presenting variability due to hot and cold spots, extinction by circumstellar material, and changes in the disk emission in the near-infrared. We contemplated using the use of near- infrared variability to identify disk-bearing stars and verified that 53.4% of the known disk-bearing stars in our sample could have been identified as such based solely on their variability. We present 18 newly identified disk- bearing stars and 14 eclipsing binary candidates among CygOB2 lower-mass members.2020A&A...640A.128Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/640/A128CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/773/135 : Disk-bearing stars in Cygnus OB2 (Guarcello+, 2013)J/A+A/603/A106 : Rotational periods in Cygnus OB2 (Roquette+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/640/A128https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/640/A128http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/640/A128https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/640/A128https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/640/A128http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/640/A128GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/640/A128/table1-5 (Paper's tables 1 to 5)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/640/A128/table1-5?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/640/A128/table1-5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/640/A128/table1-5?GETtext/xml+votable180.050000true308.0141541.309380.0055555555555555566/14670-14671 14692-146948.297946179207444e-20 1.6867587740958882e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/640/A128?format=asciiInfrareddefaultJ/A+A/640/A128/table1-5Paper's tables 1 to 5recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLCShow the light curvesmeta.ref.urlcharID[1/155618] Internal identifiermeta.id;meta.mainintGDW15[119/5699]? Internal identifier in Guarcello et al., 2015 (2015arXiv150103761G)meta.idintnullableGDW13[229/326542]? Internal identifier in Guarcello et al., 2013 (J/ApJ/773/135)meta.idintnullableRAJ2000Right ascension (J2000.0)degpos.eq.ra;meta.mainDEJ2000Declination (J2000.0)degpos.eq.dec;meta.mainStet[-0.11/15.64]? Stetson Variability Indexmeta.code;src.var.indexfloatnullableSx[0/2]? Stetson Index selection flag (1)meta.codeintnullableType[1/3]? Light-curve morphology type (2)src.morph.typeintnullableAsymm[+/-] Light Curve Symetry (3)spect.line.asymmetrycharDisk[0/1]? Disk flag (4)meta.codeintnullablePer? Detected Period (5)dtime.periodfloatnullableCompound[1/5]? Compound flag (6)meta.codeintnullableSlope[1]? Slope Flag (7)meta.codeintnullablenJ[0/107] Number of J observationsmeta.numberintnH[0/104] Number of H observationsmeta.numberintnK[0/104] Number of K observationsmeta.numberintJmag[10.45/18.83]? Median UKIRT/WFCAM J magnitudemagphot.mag;em.IR.JfloatnullableHmag[9.65/18.17]? Median UKIRT/WFCAM H magnitudemagphot.mag;em.IR.HfloatnullableKmag[9.15/17.47]? Median UKIRT/WFCAM K magnitudemagphot.mag;em.IR.Kfloatnullablee_Jmag[0.02/0.1]? Representative uncertainty in Jmagstat.error;phot.magfloatnullablee_Hmag[0.02/0.38]? Representative uncertainty in Hmagstat.error;phot.magfloatnullablee_Kmag[0.02/0.09]? Representative uncertainty in Kmagstat.error;phot.magfloatnullableJ-H[0.23/3.54]? Median J-H colormagphot.color;em.IR.J;em.IR.HfloatnullableJ-K[0.33/5.94]? Median J-K colormagphot.color;em.IR.J;em.IR.KfloatnullableH-K[0.06/2.4]? Median H-K colormagphot.color;em.IR.H;em.IR.Kfloatnullablee_J-H[0.03/0.12]? Representative J-H uncertaintymagstat.error;phot.color;em.IR.Jfloatnullablee_J-K[0.03/0.13]? Representative J-K uncertaintymagstat.error;phot.color;em.IR.Jfloatnullablee_H-K[0.03/0.13]? Representative H-K uncertaintymagstat.error;phot.color;em.IR.HfloatnullableJamp[0.02/1.79]? Peak-to-peak J amplitudemagsrc.var.amplitudefloatnullableHamp[0.02/1.84]? Peak-to-peak H amplitudemagsrc.var.amplitudefloatnullableKamp[0.02/1.61]? Peak-to-peak K amplitudemagsrc.var.amplitudefloatnullableJ-Hamp[0.02/0.72]? Peak-to-peak J-H amplitudemagsrc.var.amplitudefloatnullableJ-Kamp[0.01/1.08]? Peak-to-peak J-K amplitudemagsrc.var.amplitudefloatnullableH-Kamp[0.01/0.97]? Peak-to-peak H-K amplitudemagsrc.var.amplitudefloatnullablermsJamp[0.02/1.29]? rms J amplitudemagstat.errorfloatnullablermsHamp[0.02/1.32]? rms H amplitudemagstat.errorfloatnullablermsKamp[0.02/1.14]? rms K amplitudemagstat.errorfloatnullablermsJ-Hamp[0.01/0.27]? rms J-H amplitudemagstat.errorfloatnullablermsJ-Kamp[0.01/0.39]? rms J-K amplitudemagstat.errorfloatnullablermsH-Kamp[0.01/0.35]? rms H-K amplitudemagstat.errorfloatnullableIncKHK[-79.5/74.2]? The K,(H-K) slopedegspect.indexfloatnullableIncJJH[-58.3/80.5]? The J,(J-H) slopedegspect.indexfloatnullableIncJHHK[21/57.5]? The (J-H),(H-K) slopedegspect.indexfloatnullablee_IncJHHK[0./0.8]? Uncertainty in IncJHHKdegstat.errorfloatnullablee_IncKHK[0.5/9.4]? Uncertainty in IncKHKdegstat.errorfloatnullablee_IncJJH[0.2/7.5]? Uncertainty in IncJJHdegstat.errorfloatnullable