J/ApJ/802/59ivo://CDS.VizieR/J/ApJ/802/59doi:10.26093/cds/vizier.18020059CDSKim H.-J.Koo B.-C.Davis C.J.2017-12-06T07:38:11Z2015-08-24T14:22:33ZCDS support team

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

cds-question@unistra.frmolecular-cloudsinfrared-photometryyoung-stellar-objectsWe present star formation activity in the infrared dark cloud (IRDC) G53.2, a remarkable IRDC located at Galactic coordinates (l,b)~(53.2{deg},0.0{deg}) based on the census of young stellar object (YSO) candidates. IRDC G53.2 was previously identified as several IRDCs in mid-IR images, but it is in fact a long (>~45pc) cloud, well consistent with a CO cloud at v~23km/s (or at d~1.7kpc). We present a point-source catalog of IRDC G53.2 that contains ~370 sources from our photometry of the Spitzer MIPS 24{mu}m data and Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) Catalog. The classification of the identified sources based on their spectral index and control field analysis to remove field star contamination reveals that IRDC G53.2 is an active star-forming region with ~300 YSO candidates. We compare the YSO classification based on spectral index, mid-IR colors, and the wavelength range used, which results in consistent classification, except for flat-spectrum objects, with some ambiguity between Class I and II. Comparison of the YSO population in IRDC G53.2 with those of other nearby star-forming clusters indicates that they are similar in age; on the other hand, stronger association with mid-IR stellar sources in IRDC G53.2 compared with other IRDCs indicates that IRDC G53.2 is at a later evolutionary stage among IRDCs. Spatial distribution of the YSO candidates in IRDC G53.2 shows a good correlation with ^13^CO column density and far-IR emission, and earlier-class objects tend to be more clustered in the regions with higher density.2015ApJ...802...59Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/802/59CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/293 : GLIMPSE Source Catalog (I + II + 3D) (IPAC 2008)VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)V/114 : MSX6C Infrared Point Source Catalog (Egan+ 2003)II/316 : UKIDSS-DR6 Galactic Plane Survey (Lucas+ 2012)J/AJ/149/64 : MIPSGAL 24{mu}m point source catalog (Gutermuth+, 2015)J/ApJS/193/25 : The NAN complex. II. MIPS observations (Rebull+, 2011)J/ApJ/723/492 : Physical properties of GRS mol. clouds (Roman-Duval+, 2010)J/A+A/505/405 : A catalogue of Spitzer dark clouds (Peretto+, 2009)J/ApJS/184/18 : Spitzer survey of young stellar clusters (Gutermuth+, 2009)J/ApJ/699/1092 : Giant molecular clouds (SRBY) (Heyer+, 2009)J/ApJ/698/324 : Spitzer IRDCs (Ragan+, 2009)J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)J/ApJ/653/1325 : Galactic distribution of infrared dark clouds (Simon+, 2006)J/ApJ/641/389 : Millimetric observations of IRDC cores (Rathborne+, 2006)J/ApJ/639/227 : MSX IRDC candidate catalog (Simon+, 2006)http://www.astro.wisc.edu/glimpse/glimpsedata.html : GLIMPSE home pagehttp://www.ipac.caltech.edu/2mass/releases/allsky/ : 2MASS all-sky home pagehttp://irsa.ipac.caltech.edu/data/SPITZER/MIPSGAL/ : MIPSGAL on NASA/IPAC IRSAhttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/802/59https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/802/59http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/802/59https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/802/59https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/802/59http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/802/59GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/802/59/table2 (Point-source catalog of IRDC G53.2)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/802/59/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/802/59/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/802/59/table2?GETtext/xml+votable180.050000true292.58162518.30478060.0055555555555555565/76796.772611666688002e-21 1.7003137259100215e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/802/59?format=asciiInfrareddefaultJ/ApJ/802/59/table2Point-source catalog of IRDC G53.2SimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/369] Running sequence numbermeta.id;meta.mainintprimaryRAJ2000[19] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[17/18] Degree of Declination (J2000)pos.eq.dec;meta.mainJmag[7.7/17.6]? 2MASS J band magnitudemagphot.mag;em.IR.Jfloatnullablee_Jmag[0.01/0.3]? Uncertainty in Jmagmagstat.error;phot.mag;em.IR.JfloatnullableHmag? 2MASS H band magnitudemagphot.mag;em.IR.Hfloatnullablee_Hmag? Uncertainty in Hmagmagstat.error;phot.mag;em.IR.HfloatnullableKmag[4.4/14.9]? 2MASS Ks band magnitudemagphot.mag;em.IR.Kfloatnullablee_Kmag[0.01/10]? Uncertainty in Kmagmagstat.error;phot.mag;em.IR.Kfloatnullable[3.6]? Spitzer/IRAC 3.6 micron band magnitudemagphot.mag;em.IR.3-4umfloatnullablee_[3.6]? Uncertainty in [3.6]magstat.errorfloatnullable[4.5]? Spitzer/IRAC 4.5 micron band magnitudemagphot.mag;em.IR.4-8umfloatnullablee_[4.5]? Uncertainty in [4.5]magstat.errorfloatnullable[5.8]? Spitzer/IRAC 5.8 micron band magnitudemagphot.flux.density;em.IR.4-8umfloatnullablee_[5.8]? Uncertainty in [5.8]magstat.errorfloatnullable[8.0][3.4/12.3]? Spitzer/IRAC 8.0um band magnitudemagphot.flux.density;em.IR.8-15umfloatnullablee_[8.0][0.01/0.4]? Uncertainty in [8.0]magstat.errorfloatnullable[24][0.5/8.5]? Spitzer/MIPS 24um band magnitudemagphot.flux.density;em.IR.15-30umfloatnullablee_[24][0.04/0.08]? Uncertainty in [24]magstat.errorfloatnullablealpha[-2.9/2.4]? Infrared spectral index {alpha} (1)spect.index;em.IRfloatnullablee_alpha[0.02/0.7]? The 1{sigma} uncertainty in alphastat.error;pos.eq.rafloatnullableClassClassification: I, II, III, "Flat", "Phot", or "No Class" (1)src.classcharn_Class[ad, ] Note(s) on origin or nature of source (2)meta.notecharGLIMPSESources within 2" from GLIMPSE (II/293)meta.ref.urlintnullableUKIDSSSources within 1.5" from UKIDSS-DR6 GPS (II/316)meta.ref.urlintnullableMIPSGALSources within 1.5" from Gutermuth+, 2015, J/AJ/149/64meta.ref.urlintnullable