J/MNRAS/473/2222ivo://CDS.VizieR/J/MNRAS/473/2222doi:10.26093/cds/vizier.74732222CDSHeyer M.Wilson G.W.Gutermuth R.Lizano S.Gomez-Ruiz A.Kurtz S.,Luna A.Serrano Bernal E.O.Schloerb F.P.2024-08-17T20:21:28Z2021-02-10T14:57:12ZCDS support team

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

cds-question@unistra.frgalaxy-planesmilky-way-galaxyinterstellar-mediummillimeter-astronomysubmillimeter-astronomymolecular-cloudsSensitive, imaging observations of the {lambda}1.1mm dust continuum emission from a 1deg^2^ area collected with the AzTEC bolometer camera on the Large Millimeter Telescope are presented. A catalogue of 1545 compact sources is constructed based on a Wiener-optimization filter. These sources are linked to larger clump structures identified in the Bolocam Galactic Plane Survey. Hydrogen column densities are calculated for all sources and mass and mean volume densities are derived for the subset of sources for which kinematic distances can be assigned. The AzTEC sources are localized, high-density peaks within the massive clumps of molecular clouds and comprise 5-15 per cent of the clump mass. We examine the role of the gravitational instability in generating these fragments by comparing the mass of embedded AzTEC sources to the Jeans mass of the parent BGPS object. For sources with distances less than 6kpc the fragment masses are comparable to the clump Jeans mass, despite having isothermal Mach numbers between 1.6 and 7.2. AzTEC sources linked to ultra compact HII regions have mass surface densities greater than the critical value implied by the mass-size relationship of infrared dark clouds with high-mass star formation, while AzTEC sources associated with Class II methanol masers have mass surface densities greater than 0.7gcm^-2^ that approaches the proposed threshold required to form massive stars.2018MNRAS.473.2222Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/473/2222CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/799/29 : BGPS. XII. DR2 distance catalog (Ellsworth-Bowers+, 2015)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/473/2222https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/473/2222http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/473/2222https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/473/2222https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/473/2222http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/473/2222GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/473/2222/table1 (Identified AzTEC sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/473/2222/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/473/2222/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/473/2222/table1?GETtext/xml+votable180.050000true278.4203-7.42690.0055555555555555566/29533 29535 30216 302181.8058623843283312e-22 1.8058623843283312e-22https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/473/2222?format=asciiMillimeterdefaultJ/MNRAS/473/2222/table1Identified AzTEC sourcesSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAzTECAzTEC IDmeta.id;meta.mainintNameSource name, LMT_LLL.lll+BBB.bbbmeta.idcharGLONSource position Galactic longitudedegpos.galactic.lonGLATSource position Galactic latitudedegpos.galactic.latfloatRAJ2000Source position Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Source position Declination (J2000)degpos.eq.dec;meta.mainS1.1mm1.1mm Flux densityJyphot.flux.density;em.mm.200-400GHzfloate_S1.1mm1.1mm flux density uncertaintyJystat.errorfloatlogPJLogarithm of Joint probability that source is a false detectionphot.flux.density;em.mm.200-400GHzfloatJ/MNRAS/473/2222/table2AzTEC Sources linked to BGPS objectsAzTECAzTEC IDmeta.id;meta.mainintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBGPSBGPS V2.1 Catalog Number, [ERG2015] NNNN in Simbadmeta.id.parentintVLSR? Dense gas velocity (km/s)km/sphys.veloc;pos.lsrfloatnullableDist? Distance to source (kpc)kpcpos.distancefloatnullablee_Dist? Negative tail 1 sigma distance uncertaintykpcstat.errorfloatnullableE_Dist? Positive tail 1 sigma distance uncertaintykpcstat.error;stat.maxfloatnullableKdar[FNTU] Kinematic distance ambiguity resolution flag (1)meta.codecharRef[0/5] Citation or method to distance estimate (2)meta.bibintJ/MNRAS/473/2222/table3AzTEC ^13^CO velocities and dust column densitiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAzTECAzTEC IDmeta.id;meta.mainintV13CO^13^CO velocitykm/sspect.dopplerVelocfloatCvContrast value = ratio of antenna temperatures at the peak 13CO intensity to second brightest peakstat.fit.paramfloatNHHydrogen column density1e+22cm**-2phys.columnDensityfloate_NHNegative tail 1 sigma uncertainty of hydrogen column density1e+22cm**-2stat.errorfloatE_NHPositive tail 1 sigma uncertainty of hydrogen column density1e+22cm**-2stat.error;stat.maxfloatJ/MNRAS/473/2222/table4AzTEC masses and mean volume densitiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAzTECAzTEC IDmeta.id;meta.mainintMassMasssolMassphys.massfloate_MassNegative tail 1 sigma uncertainty of masssolMassstat.error;phys.massfloatE_MassPostive tail 1 sigma uncertainty of masssolMassstat.error;stat.maxfloatnMean volume densitycm**-3phys.densitydoublee_nNegative tail 1 sigma uncertainty of Mean volume densitycm**-3stat.errordoubleE_nPostive tail 1 sigma uncertainty of Mean volume densitycm**-3stat.error;stat.maxdouble