J/ApJ/823/160ivo://CDS.VizieR/J/ApJ/823/160doi:10.26093/cds/vizier.18230160CDSDunham M.M.Offner S.S.R.Pineda J.E.Bourke T.L.Tobin J.J.,Arce H.G.Chen X.Di Francesco J.Johnstone D.Lee K.I.Myers P.C.,Price D.Sadavoy S.I.Schnee S.2018-05-14T08:34:42Z2018-02-20T06:51:55ZCDS support team

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

cds-question@unistra.frmolecular-cloudsmillimeter-astronomysubmillimeter-astronomygalaxy-classification-systemsWe present an Atacama Large Millimeter/submillimeter Array (ALMA) 106 GHz (Band 3) continuum survey of the complete population of dense cores in the Chamaeleon I molecular cloud. We detect a total of 24 continuum sources in 19 different target fields. All previously known Class 0 and Class I protostars in Chamaeleon I are detected, whereas all of the 56 starless cores in our sample are undetected. We show that the Spitzer+Herschel census of protostars in Chamaeleon I is complete, with the rate at which protostellar cores have been misclassified as starless cores calculated as <1/56, or <2%. We use synthetic observations to show that starless cores collapsing following the turbulent fragmentation scenario are detectable by our ALMA observations when their central densities exceed ~10^8^/cm^3^, with the exact density dependent on the viewing geometry. Bonnor-Ebert spheres, on the other hand, remain undetected to central densities at least as high as 10^10^/cm^3^. Our starless core non-detections are used to infer that either the star-formation rate is declining in Chamaeleon I and most of the starless cores are not collapsing, matching the findings of previous studies, or that the evolution of starless cores are more accurately described by models that develop less substructure than predicted by the turbulent fragmentation scenario, such as Bonnor-Ebert spheres. We outline future work necessary to distinguish between these two possibilities.2016ApJ...823..160Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/823/160CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/267/755 : Polarimetry in the Chamaeleon I Dark Cloud (McGregor+, 1994)J/A+A/357/219 : ISOCAM observations in Cha I. (Persi+, 2000)J/AJ/121/974 : JHK photometry in Cha I (Gomez+, 2001)J/AJ/121/2673 : 3{mu}m survey of the Chamaeleon I dark cloud (Kenyon+, 2001)J/A+A/423/1029 : XMM-Newton obs, in Cha I South (Stelzer+, 2004)J/ApJ/602/816 : Chamaeleon I star-forming region census (Luhman, 2004)J/ApJ/614/267 : Chandra sources in Cha I North (Feigelson+, 2004)J/A+A/461/669 : XMM observations of Cha I dark cloud (Robrade+, 2007)J/ApJS/173/104 : Stellar population in Chamaeleon I (Luhman, 2007)J/ApJ/675/1375 : IRAC/MIPS photometry in Cha I (Luhman+, 2008)J/ApJ/684/654 : Low-mass members of Chamaeleon I (Luhman+, 2008)J/A+A/527/A145 : Chamaeleon I 870um sources (Belloche+, 2011)J/A+A/551/A46 : Compiled photometry for Cham I and II membersJ/A+A/556/A144 : Proper motions of young stars in ChamaeleonJ/A+A/601/A97 : Gaia-ESO Survey: Cha I members (Sacco+, 2017)J/AJ/154/46 : Proper motions and photometry for members of Cha Ihttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/823/160https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/823/160http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/823/160https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/823/160https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/823/160http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/823/160GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/823/160/table1 (ALMA 106 GHz Continuum Observations)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/823/160/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/823/160/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/823/160/table1?GETtext/xml+votable180.050000true167.0134167-77.65497220.005555555555555556Cone search capability for table J/ApJ/823/160/table2 (Observed Properties of ALMA 106 GHz Continuum Detections)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/823/160/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/823/160/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/823/160/table2?GETtext/xml+votable180.050000true167.013375-77.65483330.0055555555555555566/36953 36956 36957 36958https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/823/160?format=asciiRadioOpticaldefaultJ/ApJ/823/160/table1ALMA 106 GHz Continuum ObservationsBmajSynthesized beam major axisarcsecphys.angSize;srcfloatrms1{sigma} rms of our ALMA continuum datamJy/beamstat.errorfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCHAI-[01/84] Source identifier (CHAI-NN)meta.id;meta.mainintRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainBminSynthesized beam minor axisarcsecphys.angSize;srcfloatPA[] Synthesized beam position angledegpos.posAng;instr.beamfloatsigmaM1{sigma} mass sensitivitysolMass/beamstat.fit.paramfloatStatusEvolutionary status (1)meta.codecharCat-linkDisplay data from Belloche et al., 2011, J/A+A/527/A145meta.ref.urlintnullableJ/ApJ/823/160/table2Observed Properties of ALMA 106 GHz Continuum Detectionsn_MinAxis[U] Note on MinAxis (1)meta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCHAI-Source identifier (CHAI-NN-A)meta.id;meta.maincharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainMajAxis? Deconvolved major axisarcsecphys.angSizefloatnullablee_MajAxis? Uncertainty in MajAxisarcsecstat.error;phys.angSizefloatnullablen_MajAxis[U] Note on MajAxis (1)meta.notecharMinAxis? Deconvolved minor axisarcsecphys.angSize;srcfloatnullablee_MinAxis? Uncertainty in MinAxisarcsecstat.error;phys.angSizefloatnullablePA? Deconvolved position angledegpos.posAngfloatnullablee_PA? Uncertainty in PAdegstat.errorfloatnullablen_PA[U] Note on PA (1)meta.notecharFpeakPeak flux density at 106 GHzmJy/beamphot.flux.density;em.mm.50-100GHzfloate_FpeakUncertainty in FpeakmJy/beamstat.errorfloatFintIntegrated flux density at 106 GHzmJy/beamphot.flux.density;em.mm.50-100GHzfloate_FintUncertainty in FintmJy/beamstat.errorfloat