J/ApJS/225/26ivo://CDS.VizieR/J/ApJS/225/26doi:10.26093/cds/vizier.22250026CDSKim M.-R.Lee C.W.Dunham M.M.Evans II N.J.Kim G.Allen L.E.2017-12-18T07:56:56Z2016-11-15T08:13:37ZCDS support team

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

cds-question@unistra.frinfrared-photometrymolecular-cloudsmillimeter-astronomysubmillimeter-astronomyWe present the results of a search for Very Low-Luminosity Objects (VeLLOs) in the Gould Belt (GB) clouds using infrared and sub-millimeter (sub-mm) data from 1.25 to 850{mu}m and our N_2_H^+^(J=1-0) observations. We modified the criteria by Dunham et al. (2008, J/ApJS/179/249) to select the VeLLOs in the GB clouds, finding 95 VeLLO candidates, 79 of which are newly identified in this study. Out of 95 sources, 44 were detected in both sub-mm continuum and N_2_H^+^ emission and were classified as Group A (the VeLLOs), and 51 sources detected in either sub-mm emission or N_2_H^+^ emission were classified with Group B as candidate VeLLOs. We find that these VeLLOs and the candidates are forming in environments different from those of the likely VeLLOs. Seventy-eight sources are embedded within their molecular clouds, and thus are likely VeLLOs forming in a dense environment. The remaining 17 sources are located in low-level extinction regions (A_V_<1) connected to the clouds, and can be either background sources or candidate substellar objects forming in an isolated mode. The VeLLOs and the candidates are likely more luminous and their envelopes tend to be more massive in denser environments. The VeLLOs and the candidates are more populous in the clouds where more YSOs form, indicating that they form in a manner similar to that of normal YSOs. The bolometric luminosities and temperatures of the VeLLOs are compared to predictions of episodic accretion models, showing that the low luminosities for most VeLLOs can be well explained by their status in the quiescent phases of a cycle of episodic mass accretion.2016ApJS..225...26Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/225/26CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/332 : c2d Spitzer final data release (DR4) (Evans+, 2003)J/ApJ/817/167 : JCMT Gould Belt Survey: dense cores in Orion B (Kirk+, 2016)J/A+A/584/A91 : Dense cores in Aquila from Herschel (Konyves+, 2015)J/MNRAS/448/1551 : JCMT Gould Belt Survey: Serpens MWC 297 (Rumble+, 2015)J/ApJ/786/29 : Catalog of distances to molecular clouds (Schlafly+, 2014)J/ApJ/767/36 : APEX observations of HOPS protostars (Stutz+, 2013)J/AJ/145/94 : Protostar luminosities from Spitzer surveys (Dunham+, 2013)J/ApJS/205/5 : YSO candidates in nearby molecular clouds (Hsieh+, 2013)J/AJ/144/192 : Spitzer survey of Orion A & B. I. YSO catalog (Megeath+, 2012)J/AJ/144/31 : Spitzer+2MASS photometry of protostar cand. (Kryukova+, 2012)J/A+A/527/A145 : Chamaeleon I 870um sources (Belloche+, 2011)J/PASJ/63/S1 : Atlas & catalog of dark clouds based on 2MASS (Dobashi+, 2011)J/ApJ/723/1019 : Galactic SFR and gas surface densities (Heiderman+, 2010)J/ApJS/186/259 : Taurus Spitzer survey: new candidate members (Rebull+, 2010)J/ApJS/185/198 : The Cepheus flare observed with IRAC and MIPS (Kirk+, 2009)J/ApJS/184/18 : Spitzer survey of young stellar clusters (Gutermuth+, 2009)J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)J/ApJS/179/249 : Low-luminosity embedded protostar population (Dunham+, 2008)J/A+A/487/993 : MAMBO Mapping of c2d Clouds and Cores (Kauffmann+, 2008)J/ApJS/177/551 : Spitzer c2d survey of Lupus dark clouds (Merin+, 2008)J/AJ/136/18 : LMC SAGE. New candidate YSOs (Whitney+, 2008)J/ApJ/676/427 : MIPS and IRAC data on ChaII PMS stars (Alcala+, 2008)J/ApJ/663/1149 : Spitzer survey of Serpens YSO population (Harvey+, 2007)J/AJ/133/1560 : Spitzer c2d small clouds and cores (Wu+, 2007)J/ApJ/638/293 : 1.1mm sources in the Perseus Molecular Cloud (Enoch+, 2006)J/A+A/447/609 : 1.2mm continuum observations in rho Oph cloud (Stanke+, 2006)J/ApJS/115/59 : Cepheus flare molecular clouds (Kun, 1998)J/A+A/291/943 : Protostellar cores (Ossenkopf+, 1994)J/A+A/216/44 : Walraven photometry in Sco-Cen association (De Geus+, 1989)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/225/26https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/225/26http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/225/26https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/225/26https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/225/26http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/225/26GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/225/26/groupb (*The group B VeLLO candidates; table added by CDS from physical parameters given in last column of table 3 in the paper)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/225/26/groupb?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/225/26/groupb?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/225/26/groupb?GETtext/xml+votable180.050000true60.370833341.35777780.005555555555555556Cone search capability for table J/ApJS/225/26/typeiii (The type III VeLLO candidates; table added by CDS from physical parameters given in last column of table 4 in the paper)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/225/26/typeiii?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/225/26/typeiii?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/225/26/typeiii?GETtext/xml+votable180.050000true67.077536.90972220.005555555555555556Cone search capability for table J/ApJS/225/26/table5 (*List of Group C VeLLO candidates)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/225/26/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/225/26/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/225/26/table5?GETtext/xml+votable180.050000true64.71583338.4530560.005555555555555556Cone search capability for table J/ApJS/225/26/vellosa (*The group A VeLLOs; table added by CDS from physical parameters given in last column of table 2 in the paper)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/225/26/vellosa?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/225/26/vellosa?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/225/26/vellosa?GETtext/xml+votable180.050000true52.135416731.18472220.005555555555555556Cone search capability for table J/ApJS/225/26/table1 (The Gould Belt molecular clouds searched for VeLLO candidates)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/225/26/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/225/26/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/225/26/table1?GETtext/xml+votable180.050000true53.7531.2166670.0055555555555555565/7585 6/857 859 861 1047 1048 1052 1054 1060 1072 1073 1075 1080 1159 1168 1231 1263 1264 1266 1539 1606 1636 14029 14031 14052 14053 15426 15964 15965 16129 16131 16196 16197 16203 16225 16277 21400 21402 21403 21425 21428 21430 21433 21435 21436 21438 21499 22804 22805 22848 22854 22855 22861 22873 23533 23560 29112 29647 29658 29659 29662 29663 30251 30254 30255 30337 30339 30344 30346 30352 30354 30356 30358 30359 30366 30621 36956 36957 39327 39370 39396 41099 41120 41122 41132 41133 41134 41515 41518 41822 42596 42598 42611 42614 42727 42736 42737 42738 42744 42754 42763 42785 42786 42787 42981 42989 44374 47742 47826 478282.4016587514425055e-21 1.7003137259100215e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/225/26?format=asciiInfraredRadiodefaultJ/ApJS/225/26/groupb*The group B VeLLO candidates; table added by CDS from physical parameters given in last column of table 3 in the paperrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/95] Sequential running numbermeta.idintNameSpitzer source name (JHHMMSS.s+DDMMSS or other)meta.id;meta.maincharCloudGould Belt molecular cloud identifier (as in table 1)meta.id.parentcharLint[0.002/0.3]? Internal luminosity inferred from 70um fluxsolLumphys.luminosity;em.IR.30-60umfloatnullablee_Lint[0.001/0.06]? Lint uncertaintysolLumstat.errorfloatnullableTbol[16/758] Bolometric temperatureKphys.temperatureintLbol[0.002/1.8] Bolometric temperaturesolLumphys.luminosityfloatTdust[10/40] Dust temperatureKphys.temperaturefloatl_TMB[<=] Limit flag on TMBmeta.code.errorcharTMB[0.2/5.1]? Peak main beam temperature (N_2_H^+^(1-0)) (not for type III sources)Kphys.temperature;meta.main;stat.maxfloatnullablee_TMB[0.07/0.5]? TMB uncertaintyKstat.errorfloatnullableMenv[0.0001/0.9]? Mass of the envelopesolMassphys.massfloatnullableR250[24/67]? Geometric mean of the major and minor axes of the FWHM of source envelope at 250um extracted by CSARarcsecphys.angSize;srcintnullableTypeType I, II or III (1)src.classcharSEDInteractive plot of spectrummeta.ref.urlchar_RAPositions from Spitzer names (right ascension part)degpos.eq.ra;meta.main_DEPositions from Spitzer names (declination part)degpos.eq.dec;meta.mainJ/ApJS/225/26/typeiiiThe type III VeLLO candidates; table added by CDS from physical parameters given in last column of table 4 in the paperrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/95] Sequential running numbermeta.idintNameSpitzer source name (JHHMMSS.s+DDMMSS or other)meta.id;meta.maincharCloudGould Belt molecular cloud identifier (as in table 1)meta.id.parentcharLint[0.002/0.3]? Internal luminosity inferred from 70um fluxsolLumphys.luminosity;em.IR.30-60umfloatnullablee_Lint[0.001/0.06]? Lint uncertaintysolLumstat.errorfloatnullableTbol[16/758] Bolometric temperatureKphys.temperatureintLbol[0.002/1.8] Bolometric temperaturesolLumphys.luminosityfloatTdust[10/40] Dust temperatureKphys.temperaturefloatMenv[0.0001/0.9]? Mass of the envelopesolMassphys.massfloatnullableR250[24/67]? Geometric mean of the major and minor axes of the FWHM of source envelope at 250um extracted by CSARarcsecphys.angSize;srcintnullableTypeType I, II or III (1)src.classcharSEDInteractive plot of spectrummeta.ref.urlchar_RAPositions from Spitzer names (right ascension part)degpos.eq.ra;meta.main_DEPositions from Spitzer names (declination part)degpos.eq.dec;meta.mainJ/ApJS/225/26/table2*List of the VeLLOs (Group A) fluxesRef? Reference (3)meta.ref;pos.frameintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/95] Source number (1-44 for group A (table2), 45-78 for group B (table3) and 79-95 for Type III (table4))meta.idintNameSpitzer source namemeta.id;meta.maincharFlag[d] Protobinary candidate flag (1)meta.code.errorcharlambda[0.75/33000]? Wavelengthumem.wldoublenullablel_FD[{<=}] Limit flag on FDmeta.code.errorFD[0.0004/90020]? Flux density at lambda (2)mJyphot.flux.densitydoublenullablee_FD[0/16100]? Uncertainty in FDmJystat.errordoublenullablef_FD[d] Protobinary candidate flag on FD (1)meta.codecharInst? Instrument usedinstr.setupcharJ/ApJS/225/26/table3*List of the VeLLO candidates (Group B) fluxesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/95] Source number (1-44 for group A (table2), 45-78 for group B (table3) and 79-95 for Type III (table4))meta.idintNameSpitzer source namemeta.id;meta.maincharFlag[d] Protobinary candidate flag (1)meta.code.errorcharlambda[0.75/33000]? Wavelengthumem.wldoublenullablel_FD[{<=}] Limit flag on FDmeta.code.errorcharFD[0.0004/90020]? Flux density at lambda (2)mJyphot.flux.densitydoublenullablee_FD[0/16100]? Uncertainty in FDmJystat.errordoublenullablef_FD[d] Protobinary candidate flag on FD (1)meta.codecharInst? Instrument usedinstr.setupcharRef? Reference (3)meta.ref;pos.frameintnullableJ/ApJS/225/26/table5*List of Group C VeLLO candidatesFD3.6[0.09/1073]? Spitzer/IRAC 3.6um band flux densitymJyphot.mag;em.IR.3-4umfloatnullablel_FD3.6[{<=}] Limit flag on F3.6meta.code.errorrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/97] Source numbermeta.idintNameSpitzer source name; JHHMMSS.s+DDMMSSmeta.id;meta.maincharCloudCloud identifier (as in table 1)meta.id.parentcharl_FD1.25[{<=}] Limit flag on F1.25meta.code.errorFD1.25[0.4/115]? 2MASS 1.25um band (J) flux densitymJyphot.flux.density;em.IR.Jfloatnullablee_FD1.25[0.01/4]? The 1{sigma} uncertainty in F1.25mJystat.errorfloatnullableFD1.65[0.3/314]? 2MASS 1.65um band (H) flux densitymJyphot.flux.density;em.IR.Hfloatnullablee_FD1.65[0.01/7]? The 1{sigma} uncertainty in F1.65mJystat.errorfloatnullablel_FD1.65[{<=}] Limit flag on F1.65meta.code.errorFD2.12[0.7/618]? 2MASS 2.12um band (K_S_) flux densitymJyphot.mag;em.IR.Kfloatnullablee_FD2.12[0.1/15]? The 1{sigma} uncertainty in F2.12mJystat.errorfloatnullablel_FD2.12[<=] Limit flag on F2.12meta.code.errore_FD3.6[0.01/55]? The 1{sigma} uncertainty in F3.6mJystat.errorfloatnullableFD4.5[0.1/1443]? Spitzer/IRAC 4.5um band flux densitymJyphot.mag;em.IR.4-8umfloatnullablee_FD4.5[0.01/75]? The 1{sigma} uncertainty in F4.5mJystat.errorfloatnullablel_FD4.5[{<=}] Limit flag on F4.5meta.code.errorFD5.8[0.1/1811]? Spitzer/IRAC 5.8um band flux densitymJyphot.flux.density;em.IR.4-8umfloatnullablee_FD5.8[0.03/88]? The 1{sigma} uncertainty in F5.8mJystat.errorfloatnullableFD8.0[0.01/2553]? Spitzer/IRAC 8.0um band flux densitymJyphot.flux.density;em.IR.8-15umfloatnullablee_FD8.0[0.04/5]? The 1{sigma} uncertainty in F8.0mJystat.errorfloatnullableFD24[0.5/4264] Spitzer/MIPS 24um band flux densitymJyphot.flux.density;em.IR.15-30umfloate_FD24[0/446] The 1{sigma} uncertainty in F24mJystat.errorfloatFD70[8/5320] Spitzer/MIPS 70um band flux densitymJyphot.flux.density;em.IR.30-60uminte_FD70[0/573]? The 1{sigma} uncertainty in F70mJystat.errorintnullableLInt[0.001/0.3] Integrated luminositysolLumphys.luminosity;em.IRfloate_LInt[0.001/0.1] The 1{sigma} uncertainty in LIntsolLumstat.errorfloat_RAPositions from Spitzer names (right ascension part)degpos.eq.ra;meta.main_DEPositions from Spitzer names (declination part)degpos.eq.dec;meta.mainJ/ApJS/225/26/table4List of Type III VeLLO candidates fluxesFlag[d] Protobinary candidate flag (1)meta.code.errorcharlambda[0.75/33000]? Wavelengthumem.wldoublenullablel_FD[{<=}] Limit flag on FDmeta.code.errorcharFD[0.0004/90020]? Flux density at lambda (2)mJyphot.flux.densitydoublenullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/95] Source number (1-44 for group A (table2), 45-78 for group B (table3) and 79-95 for Type III (table4))meta.idintNameSpitzer source namemeta.id;meta.mainchare_FD[0/16100]? Uncertainty in FDmJystat.errordoublenullablef_FD[d] Protobinary candidate flag on FD (1)meta.codecharInst? Instrument usedinstr.setupcharRef? Reference (3)meta.ref;pos.frameintnullableJ/ApJS/225/26/vellosa*The group A VeLLOs; table added by CDS from physical parameters given in last column of table 2 in the paperrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/95] Sequential running numbermeta.idintNameSpitzer source name (JHHMMSS.s+DDMMSS or other)meta.id;meta.maincharCloudGould Belt molecular cloud identifier (as in table 1)meta.id.parentcharLint[0.002/0.3]? Internal luminosity inferred from 70um fluxsolLumphys.luminosity;em.IR.30-60umfloatnullablee_Lint[0.001/0.06]? Lint uncertaintysolLumstat.errorfloatnullableTbol[16/758] Bolometric temperatureKphys.temperatureintLbol[0.002/1.8] Bolometric temperaturesolLumphys.luminosityfloatTdust[10/40] Dust temperatureKphys.temperaturefloatl_TMB[<=] Limit flag on TMBmeta.code.errorcharTMB[0.2/5.1]? Peak main beam temperature (N_2_H^+^(1-0)) (not for type III sources)Kphys.temperature;meta.main;stat.maxfloatnullablee_TMB[0.07/0.5]? TMB uncertaintyKstat.errorfloatnullabledelV[0.2/1]? N_2_H^+^_ line velocity ({Delta}V_N_2_H^+^_) (only for group A)km/sspect.dopplerVelocfloatnullablee_delV[0.01/0.4]? delV uncertaintykm/sstat.errorfloatnullableMenv[0.0001/0.9]? Mass of the envelopesolMassphys.massfloatnullableR250[24/67]? Geometric mean of the major and minor axes of the FWHM of source envelope at 250um extracted by CSARarcsecphys.angSize;srcintnullableTypeType I, II or III (1)src.classcharSCatDisplay Spitzer data from (Evans+, 2003, II/332 and 2009, J/ApJS/181/321; Dunham+, 2008, J/ApJS/179/249 and 2013, J/AJ/145/94) within 0.5"meta.ref.urlintnullableSEDInteractive plot of spectrummeta.ref.urlchar_RAPositions from Spitzer names (from author for "CB130-3") or from SIMBAD (right ascension part)degpos.eq.ra;meta.main_DEPositions from Spitzer names (from author for "CB130-3") or from SIMBAD (declination part)degpos.eq.dec;meta.mainJ/ApJS/225/26/table1The Gould Belt molecular clouds searched for VeLLO candidatesSimbadNameSimbad column added by the CDSmeta.idcharNaNumber of sources in group A (VELLO) for this cloudmeta.numberintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_Cloud[c] c=small coremeta.codecharCloudGould Belt molecular cloud or small coresmeta.id;meta.maincharprimaryProjectProject identifiermeta.idcharDist[125/450] Distance (or lower range if Dist2 exists)pcpos.distance;pos.heliocentricintDist2[325]? Upper range of Distancepcpos.distance;pos.heliocentricintnullablee_Dist[2/100]? Distance uncertaintypcstat.errorintnullabler_Dist[1/16] Distance reference (1)meta.ref;pos.frameintNyso[4/3479]? Number of YSOs (2)meta.numberintnullableNV[0/28] Number of VeLLOs from this studymeta.numberintNT3Number of type III sources (VELLO candidates) for this cloudmeta.numberintnullableNbNumber of sources in group B (VELLO candidates) for this cloudmeta.numberintnullableNcNumber of sources in group C for this cloudmeta.numberintnullableAv[2.1/12.4]? V-band extinctionphys.absorption;em.opt.Vfloatnullabler_Av[1/4]? Av reference (3)meta.ref;pos.frameintnullable_RAPositions from SIMBAD or from http://irsa.ipac.caltech.edu/data/SPITZER/C2D/cores.html for the cores (right ascension part)degpos.eq.ra;meta.mainnullable_DEPositions from SIMBAD or from http://irsa.ipac.caltech.edu/data/SPITZER/C2D/cores.html for the cores (declination part)degpos.eq.dec;meta.mainnullable