J/AJ/155/99ivo://CDS.VizieR/J/AJ/155/99doi:10.26093/cds/vizier.51550099CDSWolk S.J.Gunther H.M.Poppenhaeger K.Winston E.Rebull L.M.,Stauffer J.R.Gutermuth R.A.Cody A.M.Hillenbrand L.A.Plavchan P.,Covey K.R.Song I.2021-02-18T07:46:14Z2018-10-30T09:03:01ZCDS support team

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

cds-question@unistra.fropen-star-clustersstar-forming-regionsyoung-stellar-objectsinfrared-photometryvariable-starsWe present a time-variability study of young stellar objects (YSOs) in the Serpens South cluster performed at 3.6 and 4.5 {mu}m with the Spitzer Space Telescope; this study is part of the Young Stellar Object VARiability project. We have collected light curves for more than 1500 sources, including 85 cluster members, over 38 days. This includes 44 class I sources, 19 sources with flat spectral energy distributions (SEDs), 17 class II sources, and five diskless YSO candidates. We find a high variability fraction among embedded cluster members of ~70%, whereas young stars without a detectable disk display no variability. We detect periodic variability for 32 sources with periods primarily in the range of 0.2-14 days and a subset of fast rotators thought to be field binaries. The timescale for brightness changes are shortest for stars with the most photospheric SEDs and longest for those with flat or rising SEDs. While most variable YSOs become redder when fainter, as would be expected from variable extinction, about 10% get bluer as they get fainter. One source, SSTYSV J183006.13-020108.0, exhibits "cyclical" color changes.2018AJ....155...99Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/155/99CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)J/A+A/421/623 : ISOCAM survey of YSOs in Serpens Cloud Core (Kaas+, 2004)J/A+A/463/275 : Chandra obs. of Serpens star-forming region (Giardino+, 2007)J/ApJ/663/1149 : Spitzer survey of Serpens YSO population (Harvey+, 2007)J/ApJ/669/493 : Spitzer/Chandra YSOs in Serpens cloud core (Winston+, 2007)J/ApJ/691/672 : Spectrocopy of YSOs in Serpens molecular cloudJ/ApJ/692/973 : Protostars in Perseus, Serpens and Ophiuchus (Enoch+, 2009)J/ApJS/184/18 : Spitzer survey of young stellar clusters (Gutermuth+, 2009)J/ApJ/714/778 : YSOs in the Serpens Molecular Cloud (Oliveira+, 2010)J/AJ/149/103 : Spectroscopy of candidate YSOs in Serpens (Erickson+, 2015)J/A+A/615/A9 : Distribution of Serpens South protostars (Plunkett+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/155/99https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/155/99http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/155/99https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/155/99https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/155/99http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/155/99GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/155/99/table1 (*Source designations, flux densities and lightcurve properties of sources rejected)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/155/99/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/155/99/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/155/99/table1?GETtext/xml+votable180.050000true277.4571136-1.9257989640.005555555555555556Cone search capability for table J/AJ/155/99/table2 (Source designations, flux densities and lightcurve properties of the sources used in this study)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/155/99/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/155/99/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/155/99/table2?GETtext/xml+votable180.050000true277.4396657-1.9012264450.0055555555555555566/30341 303433.9193497546148093e-20 1.7003137259100215e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/155/99?format=asciiInfrareddefaultJ/AJ/155/99/table1*Source designations, flux densities and lightcurve properties of sources rejectedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainIAUIAU designation within YSOVAR program (SSTYSV JHHMMSS.ss DDMMSS.s)meta.id;meta.maincharUKIDSSUKIDSS designationmeta.idcharKmag[14.437/18.916]? UKIDSS K band 1" aperture magnitudemagphot.mag;em.IR.Kfloatnullablee_Kmag[0.007/0.335]? Statistical error in Kmagmagstat.error;phot.magfloatnullableSClass[F I II III] IR class according to SED slope (G1)src.classchar3.6mag[12.29/16.33]? Median Spitzer/IRAC 3.6 micron band magnitudemagphot.mag;em.IR.3-4umfloatnullableo_3.6mag[0/82] Number of data point(s) in 3.6magmeta.numberint4.5mag[10.88/15.99]? Median Spitzer/IRAC 4.5 micron band magnitudemagphot.mag;em.IR.4-8umfloatnullableo_4.5mag[0/82] Number of data point(s) in 4.5magmeta.numberint3.6magmean[12.29/16.34]? Mean Spitzer/IRAC 3.6 micron band magnitudemagphot.mag;em.IR.3-4umfloatnullable4.5magmean[10.88/15.97]? Mean Spitzer/IRAC 4.5 micron band magnitudemagphot.mag;em.IR.4-8umfloatnullableDelta3.6[0.07/0.93]? Distribution width from 10-90% in 3.6magmagstat.stdevfloatnullableDelta4.5[0.04/0.94]? Distribution width from 10-90% in 4.5magmagstat.stdevfloatnullableStetson[-0.96/4.07]? Stetson index for 3.6 and 4.5 micron band lightcurvemeta.code;spect.indexfloatnullablechi2(3.6)[0.18/846.3]? Reduced {chi}^2^ to mean in 3.6magstat.fit.chi2floatnullablechi2(4.5)[0.06/59.67]? Reduced {chi}^2^ to mean in 4.5magstat.fit.chi2floatnullableCTime3.6[0.3/9.5]? Decay time of autocorrelation function (ACF) in 3.6magdstat.fit.paramfloatnullableCTime4.5[0.4/9.9]? Decay time of ACF in 4.5magdstat.fit.paramfloatnullableJ/AJ/155/99/table2Source designations, flux densities and lightcurve properties of the sources used in this studyrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainIAUIAU designation within YSOVAR program (SSTYSV JHHMMSS.ss DDMMSS.s)meta.id;meta.maincharCClass[-100/99]? IR class according to color cuts (G3)src.classintnullableSClass[F I II III] IR class according to SED slope (G1)src.classcharSSet[TRUE FALSE] Source is in YSOVAR standard set (G2)meta.codecharASet[TRUE FALSE] Source is in YSOVAR augmented set (1)meta.codecharVar[TRUE FALSE] Source is variablemeta.codecharX-ray[TRUE FALSE] An X-ray sourcemeta.codechar3.6mag[7.43/16.58]? Median Spitzer/IRAC 3.6 micron band magnitudemagphot.mag;em.IR.3-4umfloatnullableo_3.6mag[0/104] Number of data point(s) in 3.6magmeta.numberint4.5mag[6.26/16]? Median Spitzer/IRAC 4.5 micron band magnitudemagphot.mag;em.IR.4-8umfloatnullableo_4.5mag[0/85] Number of data point(s) in 4.5magmeta.numberint3.6magmean[7.41/16.53]? Mean Spitzer/IRAC 3.6 micron band magnitudemagphot.mag;em.IR.3-4umfloatnullable4.5magmean[6.25/16]? Mean Spitzer/IRAC 4.5 micron band magnitudemagphot.mag;em.IR.4-8umfloatnullableDelta3.6[0.02/0.54]? Distribution width from 10-90% in 3.6magmagstat.stdevfloatnullableDelta4.5[0.01/0.62]? Distribution width from 10-90% in 4.5magmagstat.stdevfloatnullableStetson[-0.46/15.54]? Stetson index for 3.6 and 4.5 micron band lightcurvemeta.code;spect.indexfloatnullablechi2(3.6)[0.09/269.86]? Reduced {chi}^2^ to mean in 3.6magstat.fit.chi2floatnullablechi2(4.5)[0.1/569.88]? Reduced {chi}^2^ to mean in 4.5magstat.fit.chi2floatnullablePer[0.12/13.98]? Perioddtime.periodfloatnullableCTime3.6[0.2/9.2]? Decay time of autocorrelation function (ACF) in 3.6magdstat.fit.paramfloatnullableCTime4.5[0.2/9.5]? Decay time of ACF in 4.5magdstat.fit.paramfloatnullableCMDLength[0/0.75]? Length of fitted color-magnitude diagram (CMD) vector (2)magstat.fit.paramfloatnullableCMDAngle[1.8/169.1]? Fitted CMD slope angle (2)degstat.fit.paramfloatnullablee_CMDAngle[0.4/90]? The 1{sigma} error in CMDAngledegstat.errorfloatnullableJmag[10.553/17.288]? 2MASS J band magnitudemagphot.mag;em.IR.Jfloatnullablee_Jmag[0.02/0.33]? Statistical error in Jmagmagstat.error;phot.magfloatnullableHmag[8.256/16.44]? 2MASS H band magnitudemagphot.mag;em.IR.Hfloatnullablee_Hmag[0.02/0.26]? Statistical error in Hmagmagstat.error;phot.magfloatnullableKsmag[7.193/15.403]? 2MASS K_s_ band magnitudemagphot.mag;em.IR.Kfloatnullablee_Ksmag[0.02/0.2]? Statistical error in Ksmagmagstat.error;phot.magfloatnullable3.6magC[6.54/17.75]? Cryogenic Spitzer/IRAC 3.6 micron band magnitudemagphot.mag;em.IR.3-4umfloatnullablee_3.6magC[0/0.49]? Statistical error in 3.6magCmagstat.errorfloatnullable4.5magC[6.41/16.65]? Cryogenic Spitzer/IRAC 4.5 micron band magnitudemagphot.mag;em.IR.4-8umfloatnullablee_4.5magC[0/0.28]? Statistical error in 4.5magCmagstat.errorfloatnullable5.8magC[5.51/15.74]? Cryogenic Spitzer/IRAC 5.8 micron band magnitudemagphot.flux.density;em.IR.4-8umfloatnullablee_5.8magC[0/0.5]? Statistical error in 5.8magCmagstat.errorfloatnullable8.0magC[4.28/14.68]? Cryogenic Spitzer/IRAC 8.0 micron band magnitudemagphot.flux.density;em.IR.8-15umfloatnullablee_8.0magC[0/0.73]? Statistical error in 8.0magCmagstat.errorfloatnullable24magC[0.59/9.88]? Cryogenic Spitzer/MIPS 24 micron band magnitudemagphot.flux.density;em.IR.15-30umfloatnullablee_24magC[0/0.3]? Statistical error in 24magCmagstat.errorfloatnullableAK[0/6.86] Extinction in K bandmagphys.absorptionfloatKmag[10.108/18.668]? UKIDSS K band 1" aperture magnitudemagphot.mag;em.IR.Kfloatnullablee_Kmag[0/0.241]? Statistical error in Kmagmagstat.error;phot.magfloatnullableUKIDSSUKIDSS designationmeta.idcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/AJ/155/99/table3Properties of periodic sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIAUIAU designation within YSOVAR program (SSTYSV JHHMMSS.ss DDMMSS.s)meta.id;meta.maincharXray[Yes No] An Xray source?meta.codecharSSet[Yes No] Part of the standard set of cluster members? (G2)meta.codecharPer[0.12/13.98] Perioddtime.periodfloate_Per[0/1.02]? Uncertainty in Perdstat.errorfloatnullableFAP[0/0.061] False alarm probabilitystat.fit.goodnessfloatPower[11.49/25.9] Power of the periodogram peakstat.fit.goodnessfloatGClass[-100/99] Color class from Gutermuth et al. (2009, J/ApJS/184/18) (G3)src.classintSClass[F I II III] The 2-24 {mu}m SED slope class (G1)src.classcharFilt1First filter/color ([3.6]-[4.5]) used (1)meta.codecharn_Filt1[p] Note on Filt1 (p=Filter used for the period value) (1)meta.notecharFilt2[45]? Second filter used (1)meta.code;instr.filterintnullablen_Filt2[p] Note on Filt2 (p=Filter used for the period value) (1)meta.notecharFilt3Third color ([3.6]-[4.5]) used (1)meta.codecharJ/AJ/155/99/table6Properties of the eight stars with Stetson index > 5recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIAUIAU designation within YSOVAR program (SSTYSV JHHMMSS.ss DDMMSS.s)meta.id;meta.maincharCClass[1/2] IR class according to color cutssrc.classintSClass[F I II] IR class according to SED slope (G1)src.classchar3.6mag[7.43/13.73] Median Spitzer/IRAC 3.6 micron band magnitudemagphot.mag;em.IR.3-4umfloate_3.6mag[0.18/0.54] Uncertainty in 3.6magmagstat.errorfloat4.5mag[6.26/12.17] Median Spitzer/IRAC 4.5 micron band magnitudemagphot.mag;em.IR.4-8umfloate_4.5mag[0.18/0.48] Uncertainty in 4.5magmagstat.errorfloatStetson[5.42/15.54] Stetson index for 3.6 and 4.5 micron band lightcurvemeta.code;spect.indexfloatCMDAngle[75.54/95.99] Fitted color-magnitude diagram (CMD) slope angledegstat.fit.paramfloate_CMDAngle[0.43/4.18] Uncertainty in CMDAngledegstat.errorfloat