J/MNRAS/422/1071ivo://CDS.VizieR/J/MNRAS/422/1071doi:10.26093/cds/vizier.74221071CDSWilcock L.A.Ward-Thompson D.Kirk J.M.Stamatellos D.Whitworth A.,Elia D.Fuller G.A.Di Giorgio A.Griffin M.J.Molinari S.Martin P.,Mottram J.C.Peretto N.Pestalozzi M.Schisano E.Plume R.Smith H.A.,Thompson M.A.2024-07-17T20:15:32Z2013-02-11T08:14:01ZCDS support team

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

cds-question@unistra.frinfrared-sourcesmolecular-cloudsWe have used data taken as part of the Herschel infrared Galactic Plane survey (Hi-GAL) to study 3171 infrared dark cloud (IRDC) candidates that were identified in the mid-IR (8um) by Spitzer (we refer to these as 'Spitzer-dark' regions). They all lie in the range l=300-330{deg} and |b|<=1{deg}. Of these, only 1205 were seen in emission in the far-IR (250-500um) by Herschel (we call these 'Herschel-bright' clouds). It is predicted that a dense cloud will not only be seen in absorption in the mid-IR, but will also be seen in emission in the far-IR at the longest Herschel wavebands (250-500um). If a region is dark at all wavelengths throughout the mid-IR and far-IR, then it is most likely to be simply a region of lower background IR emission (a 'hole in the sky'). Hence, it appears that previous surveys, based on Spitzer and other mid-IR data alone, may have overestimated the total IRDC population by a factor of ~2. This has implications for estimates of the star formation rate in IRDCs in the Galaxy. We studied the 1205 Herschel-bright IRDCs at 250um and found that 972 of them had at least one clearly defined 250-um peak, indicating that they contained one or more dense cores. Of these, 653 (67 per cent) contained an 8-um point source somewhere within the cloud, 149 (15 per cent) contained a 24-um point source but no 8-um source and 170 (18 per cent) contained no 24- or 8-um point sources. We use these statistics to make inferences about the lifetimes of the various evolutionary stages of IRDCs.2012MNRAS.422.1071Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/422/1071CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/505/405 : A catalogue of Spitzer dark clouds (Peretto+, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/422/1071https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/422/1071http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/422/1071https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/422/1071https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/422/1071http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/422/1071GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/422/1071/tablea1 (The 1204 IRDCs which were found to be Herschel-bright)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/422/1071/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/422/1071/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/422/1071/tablea1?GETtext/xml+votable180.050000true187.13-63.110.0055555555555555565/10419-10420 10444 10450-10451 10453 10624 6/41595 41597 41599 41653 41655 41657-41662 41670-41671 41673-41675 41684-41686 41688-41689 41696-41697 41755 41758-41759 41763 41765-41770 41772-41773 41780-41782 41809-41811 41816-41817 41820-41821 41824-41825 41856 42155 42158 42500 42502 43013-43015 43021 43024 43026https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/422/1071?format=asciiInfrareddefaultJ/MNRAS/422/1071/tablea1The 1204 IRDCs which were found to be Herschel-brightComAdditional comments (2)meta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIRDCIRDC name (LLL.lll-B.bbb) (1)meta.id;meta.maincharm_IRDC[ABC] Multiplicity index on IRDCmeta.code.multipcharRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.main8um[Yes/No ] contains an 8{mu}m source ?meta.codechar24um[Yes/No ] contains an 24{mu}m source ?meta.codecharSimbadSimbad column added by the CDSmeta.refchar