J/ApJ/878/7ivo://CDS.VizieR/J/ApJ/878/7doi:10.26093/cds/vizier.18780007CDSMeng H.Y.A.Rieke G.H.Kim J.S.Sicilia-Aguilar A.Cross N.J.G.,Esplin T.Rebull L.M.Hodapp K.W.2021-06-17T12:51:19Z2020-12-21T08:00:19ZCDS support team

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

cds-question@unistra.fropen-star-clustersinfrared-photometryvariable-starsstellar-spectral-typesWe have monitored nearly a square degree in IC 1396A/Tr 37 over 21 epochs extending over 2014-2016 for sources variable in the JHK bands. In our data, 65%+/-8% of previously identified cluster members show variations, compared with <=0.3% of field stars. We identify 119 members of Tr 37 on the basis of variability, forming an unbiased sample down to the brown dwarf regime. The K-band luminosity function in Tr 37 is similar to that of IC 348 but shifted to somewhat brighter values, implying that the K- and M-type members of Tr 37 are younger than those in IC 348. We introduce methods to classify the causes of variability, based on behavior in the color-color and color-magnitude diagrams. Accretion hot spots cause larger variations at J than at K with substantial scatter in the diagrams; there are at least a dozen, with the most active resembling EXors. Eleven sources are probably dominated by intervention of dust clumps in their circumstellar disks, with color behavior indicating the presence of grains larger than for interstellar dust, presumably due to grain growth in their disks. Thirteen sources have larger variations at K than at J or H. For 11 of them, the temperature fitted to the variable component is very close to 2000K, suggesting that the changes in output are caused by turbulence at the inner rim of the circumstellar disk exposing previously protected populations of grains.2019ApJ...878....7Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/878/7CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)J/AJ/116/1816 : JHKLMNOPQ photometry in Orion cluster (Hillenbrand+, 1998)J/AJ/121/3160 : JHK photometry near the Trapezium region (Carpenter+, 2001)J/ApJ/593/1093 : IC 348 membership (Luhman+, 2003)J/AJ/128/805 : Low-mass stars in Cepheus OB2 region (Sicilia-Aguilar+ 2004)J/AJ/130/188 : Young stars in Trumpler37 & NGC7160 (Sicilia-Aguilar+, 2005)J/ApJ/638/897 : IR phot. in Trumpler 37 & NGC 7160 (Sicilia-Aguilar+, 2006)J/AJ/132/2135 : High-res. spectroscopy in Tr 37 (Sicilia-Aguilar+, 2006)J/A+A/485/155 : HK phot. of rho Oph PMS stars (Alves de Oliveira+, 2008)J/ApJS/184/18 : Spitzer survey of young stellar clusters (Gutermuth+, 2009)J/ApJ/702/1507 : Mid-IR photometry in IC 1396A (Morales-Calderon+, 2009)J/A+A/503/651 : Variables in VLT/VIMOS field in Carina (Pietrukowicz+ 2009)J/ApJS/186/111 : Spitzer observations of Taurus members (Luhman+, 2010)J/ApJ/710/597 : Accretion in disks in Cep OB2 (Sicilia-Aguilar+, 2010)J/MNRAS/415/103 : IPHAS T Tauri candidates in IC 1396 (Barentsen+, 2011)J/ApJ/733/50 : MIR phot. monitoring of the ONC (Morales-Calderon+, 2011)J/MNRAS/426/2917 : X-rays sources in Trumpler 37 (Getman+, 2012)J/AJ/144/192 : Spitzer survey of Orion A & B. I. YSOs (Megeath+, 2012)J/AJ/143/61 : H{alpha} spectroscopy in IC 1396 HII region (Nakano+, 2012)J/ApJ/750/99 : The Pan-STARRS1 photometric system (Tonry+, 2012)J/A+A/557/A77 : VR light curves of AA Tau in 2007-2013 (Bouvier+, 2013)J/AN/334/673 : The stellar content of Trumpler 37 (Errmann+, 2013)J/A+A/559/A3 : Low-mass stars in Trumpler 37 (Sicilia-Aguilar+, 2013)J/AJ/145/113 : JHK photometry in Cyg OB7. II. Variable stars (Wolk+, 2013)J/AJ/148/122 : YSOVAR: infrared photometry in Lynds 1688 (Gunther+, 2014)J/ApJS/211/3 : NIR photometry variability in {rho} Oph (Parks+, 2014)J/AJ/150/118 : YSOVAR IR phot. in IRAS 20050+2720 (Poppenhaeger+, 2015)J/AJ/150/175 : YSOVAR: infrared photometry in NGC 1333 (Rebull+, 2015)J/AJ/150/132 : JHK photometry of 1203 variables in ONC (Rice+, 2015)J/A+A/573/A19 : Cep OB2 Herschel/PACS view (Sicilia-Aguilar+, 2015)J/ApJ/823/58 : Photo-reverberation mapping of YSOs in LDN1688 (Meng+, 2016)J/ApJ/836/34 : 24um excesses in clusters & NGC2244 membership (Meng+, 2017)J/AJ/155/99 : IR variability among YSOs in Serpens cluster (Wolk+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/878/7https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/878/7http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/878/7https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/878/7https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/878/7http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/878/7GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/878/7/table3 (Member candidates of Tr 37 from the CMD and variability)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/878/7/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/878/7/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/878/7/table3?GETtext/xml+votable180.050000true323.1418361157.518568060.005555555555555556Cone search capability for table J/ApJ/878/7/table4 (Additional variable sources in the UKIRT field)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/878/7/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/878/7/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/878/7/table4?GETtext/xml+votable180.050000true323.0877138957.804996110.005555555555555556Cone search capability for table J/ApJ/878/7/table5 (Summary of variability observed in bright members of Tr 37)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/878/7/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/878/7/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/878/7/table5?GETtext/xml+votable180.050000true323.540583357.49861110.005555555555555556Cone search capability for table J/ApJ/878/7/table6 (Summary of variability observed in members of Tr 37 from Sicilia-Aguilar+ (2013, J/A+A/559/A3))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/878/7/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/878/7/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/878/7/table6?GETtext/xml+votable180.050000true324.0932619457.528101110.0055555555555555566/15475 15478 15479 15481 15484https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/878/7?format=asciiInfrareddefaultJ/ApJ/878/7/table3Member candidates of Tr 37 from the CMD and variabilityrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBSummary of variability for this bright member of Tr37 (link to Table 5)meta.ref.urlintnullableSeq[11/355] Running sequence numbermeta.id;meta.mainintprimarySC13Variability also observed in Sicilia-Aguilar+ 2013, J/A+A/559/A3 (link to Table 6)meta.ref.urlintnullableRAJ2000[323.14/324.73] Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000[57.22/58.05] Declination (J2000)degpos.eq.dec;meta.mainImag[14.2/20.9] Apparent I band magnitude (G1)magphot.mag;em.opt.IfloatJmag[12.5/18.4] UKIRT/WFCAM apparent J band magnitudemagphot.mag;em.IR.Jfloatf_Jmag[c] c= nominal error between 0.01 and 0.02 magmeta.codecharHmag[11.8/17.3] UKIRT/WFCAM apparent H band magnitudemagphot.mag;em.IR.Hfloatf_Hmag[c] c= nominal error between 0.01 and 0.02 magmeta.codecharKmag[11.3/16.4] UKIRT/WFCAM apparent K band magnitudemagphot.mag;em.IR.KfloatDelJ[0.04/1.3] Variability in the J bandmagsrc.var.amplitudefloatDelH[0.05/1.2] Variability in the H bandmagsrc.var.amplitudefloatDelK[0.05/1] Variability in the K bandmagsrc.var.amplitudefloat<S>[0.7/13.3] Mean Stetson indexmeta.code;spect.index;stat.meanfloatVTypeVariable type (G2)src.classcharf_VType[ed] Flag on VType (1)meta.codecharONamePrevious identifier (2)meta.idcharFX[0.6/49]? X-ray photon flux1e-06ph.cm**-2.s**-1phot.flux;em.X-rayfloatnullableSCCatDisplay data from Sicilia-Aguilar+, 2004, J/AJ/128/805 and 2005, J/AJ/130/188, within 3"meta.ref.urlintnullableJ/ApJ/878/7/table4Additional variable sources in the UKIRT fieldrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/359] Running sequence numbermeta.id;meta.mainintf_Seq[bc] Flag on Seq (1)meta.codecharRAJ2000[323.08/324.74] Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000[57.21/58.08] Declination (J2000)degpos.eq.dec;meta.mainImag[14.2/22.7]? Apparent I band magnitude (G1)magphot.mag;em.opt.IfloatnullableJmag[13.2/19.55] UKIRT/WFCAM apparent J band magnitudemagphot.mag;em.IR.JfloatHmag[12.84/18.66] UKIRT/WFCAM apparent H band magnitudemagphot.mag;em.IR.HfloatKmag[12.65/18.22] UKIRT/WFCAM apparent K band magnitudemagphot.mag;em.IR.KfloatDelJ[0.05/1.61] Variability in the J bandmagsrc.var.amplitudefloatDelH[0.05/1.93] Variability in the H bandmagsrc.var.amplitudefloatDelK[0.06/1.83] Variability in the K bandmagsrc.var.amplitudefloatmeanS[0.71/8.64] Mean Stetson index (Stetson 1996PASP..108..851S)meta.code;spect.index;stat.meanfloatVType[a-c] Variable type (G2)src.classcharJ/ApJ/878/7/table5Summary of variability observed in bright members of Tr 37SimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameIdentifier (<[SHB2004] Trumpler 37 NN-NNNN> in Simbad) (1)meta.id;meta.maincharf_Name[a] Flag on Name (2)meta.codecharSpTypeSpectral type from Sicilia-Aguilar+ 2006, J/AJ/132/2135src.spTypecharRAJ2000[21] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[57/58] Degree of Declination (J2000)pos.eq.dec;meta.mainRIvarRI variability typemeta.notecharJHKvarJHK variability typemeta.notecharW1W2varW1-W2 variability typemeta.notecharf_W1W2var[ i-k,] Flag(s) on W1W2var (2)meta.codecharW1-W2[-0.21/0.72]? ALLWISE (W1-W2) color indexphot.color;em.IR;em.IRfloatnullablef_W1-W2[dehi] Flag on W1-W2 (2)meta.codecharAccAccretion from Sicilia-Aguilar+ 2010, J/ApJ/710/597phys.mass.losscharMembMembership from Sicilia-Aguilar+ 2006, J/AJ/132/2135 (3)meta.code.membercharf_Memb[l] Flag on Memb (2)meta.codecharN12Display data from Nakano+, 2012, J/AJ/143/61, within 3"meta.ref.urlintnullableSCCatDisplay data from Sicilia-Aguilar+, 2006, J/AJ/132/2135 and 2010, J/ApJ/710/597 within 3"meta.ref.urlcharJ/ApJ/878/7/table6Summary of variability observed in members of Tr 37 from Sicilia-Aguilar+ (2013, J/A+A/559/A3)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDSource identifier (S13-0NN) (<[SKS2013] JHHMMSSss+DDMMSSs> in Simbad)meta.id;meta.maincharRAOdeg[324.09/324.63] Optical Right Ascension (J2000)degpos.eq.raDEOdeg[57.28/57.8] Optical Declination degrees (J2000)degpos.eq.decRAJ2000[324.09/324.63] IR Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000[57.28/57.8] IR Declination (J2000)degpos.eq.dec;meta.mainJmag[13.28/16.01] UKIRT/WFCAM apparent J band magnitudemagphot.mag;em.IR.JfloatHmag[12.42/15.31] UKIRT/WFCAM apparent H band magnitudemagphot.mag;em.IR.HfloatKmag[11.85/14.97] UKIRT/WFCAM apparent K band magnitudemagphot.mag;em.IR.KfloatJAmp[0.025/1.11] The J band amplitudemagsrc.var.amplitudefloatHAmp[0.028/0.71] The H band amplitudemagsrc.var.amplitudefloatKAmp[0.03/0.45] The K band amplitudemagsrc.var.amplitudefloatVar[NV] Variable?meta.code;src.varcharf_Var[a] a: indicates probable foreground star from Gaia parallaxmeta.codechar