J/ApJ/886/102ivo://CDS.VizieR/J/ApJ/886/102doi:10.26093/cds/vizier.18860102CDSSanhueza P.Contreras Y.Wu B.Jackson J.M.Guzman A.E.Zhang Q.,Li S.Lu X.Silva A.Izumi N.Liu T.Miura R.E.Tatematsu K.,Sakai T.Beuther H.Garay G.Ohashi S.Saito M.Nakamura F.Saigo K.,Veena V.S.Nguyen-Luong Q.Tafoya D.2025-09-05T20:02:29Z2021-05-05T12:09:15ZCDS support team

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

cds-question@unistra.frinfrared-sourcesstar-forming-regionsgalaxy-kinematicsmillimeter-astronomyphotometrysubmillimeter-astronomyThe ALMA Survey of 70{mu}m dark High-mass clumps in Early Stages (ASHES) is designed to systematically characterize the earliest stages and constrain theories of high-mass star formation. Twelve massive (>500M_{sun}_), cold (<=15K), 3.6-70{mu}m dark prestellar clump candidates, embedded in infrared dark clouds, were carefully selected in the pilot survey to be observed with the Atacama Large Millimeter/submillimeter Array (ALMA). We have mosaicked each clump (~1arcmin^2^) in continuum and line emission with the 12m, 7m, and Total Power (TP) arrays at 224GHz (1.34mm), resulting in ~1.2" resolution (~4800au, at the average source distance). As the first paper in the series, we concentrate on the continuum emission to reveal clump fragmentation. We detect 294 cores, from which 84 (29%) are categorized as protostellar based on outflow activity or "warm core" line emission. The remaining 210 (71%) are considered prestellar core candidates. The number of detected cores is independent of the mass sensitivity range of the observations and, on average, more massive clumps tend to form more cores. We find a large population of low-mass (<1M_{sun}_) cores and no high-mass (>30M_{sun}_) prestellar cores (maximum mass 11M_{sun}_). From the prestellar core mass function, we derive a power-law index of 1.17+/-0.10, which is slightly shallower than Salpeter. We used the minimum spanning tree (MST) technique to characterize the separation between cores and their spatial distribution, and to derive mass segregation ratios. While there is a range of core masses and separations detected in the sample, the mean separation and mass per clump are well explained by thermal Jeans fragmentation and are inconsistent with turbulent Jeans fragmentation. Core spatial distribution is well described by hierarchical subclustering rather than centrally peaked clustering. There is no conclusive evidence of mass segregation. We test several theoretical conditions and conclude that overall, competitive accretion and global hierarchical collapse scenarios are favored over the turbulent core accretion scenario.2019ApJ...886..102Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/886/102CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/291/943 : Protostellar cores (Ossenkopf+, 1994)J/A+A/430/137 : Close visual companions in Scorpius OB2 (Kouwenhoven+, 2005)J/ApJ/641/389 : Millimetric observations of IRDC cores (Rathborne+, 2006)J/ApJ/639/227 : MSX IRDC candidate catalog (Simon+, 2006)J/ApJ/651/L125 : H2O masers associated with IR dark cloud cores (Wang+, 2006)J/A+A/462/L17 : Dense cores in interstellar molecular clouds (Alves+, 2007)J/A+A/505/405 : A catalogue of Spitzer dark clouds (Peretto+, 2009)J/ApJS/197/25 : MALT90 pilot survey (Foster+, 2011)J/A+A/530/A118 : G29.96-0.02 and G35.20-1.74 1mm and 3mm maps (Pillai+, 2011)J/MNRAS/424/1925 : Spectrocopic Binarity of O and B type stars (Chini+, 2012)J/ApJ/756/60 : A 3mm line survey in 37 IR dark clouds (Sanhueza+, 2012)J/A+A/544/A146 : ATLASGAL cold high-mass clumps with NH_3_ (Wienen+, 2012)J/A+A/549/A45 : ATLASGAL Compact Source Catalog: 330<l<21 (Contreras+, 2013)J/ApJ/777/157 : 90GHz obs. of high-mass star-forming regions (Hoq+, 2013)J/ApJS/209/2 : The BGPS. X. Dense molecular gas (Shirley+, 2013)J/MNRAS/443/1555 : ATLASGAL massive star forming clump sample (Urquhart+, 2014)J/ApJ/780/85 : Molecular line study of IR dark clouds (Vasyunina+, 2014)J/A+A/565/A75 : ATLASGAL: dust condensations in Gal. plane (Csengeri+, 2014)J/A+A/568/A41 : ATLASGAL Compact Source Catalog: 280<l<60 (Urquhart+, 2014)J/A+A/577/A30 : SDC335.579-0.292 6, 8, 23 and 25GHz images (Avison+, 2015)J/A+A/581/A119 : Starless gas clump IRDC 18310-4 images (Beuther+, 2015)J/ApJ/815/130 : High-mass molecular clumps from MALT90 (Guzman+, 2015)J/MNRAS/450/1926 : Infall motions in massive star-forming regions (He+, 2015)J/A+A/584/A91 : Cat. of dense cores in Aquila from Herschel (Konyves+, 2015)J/MNRAS/451/3089 : Young clumps embedded in IRDC (Traficante+, 2015)J/A+A/579/A91 : ATLASGAL Galaxy massive cold dust clumps (Wienen+, 2015)J/MNRAS/456/2041 : Fragmentation in filamentary mol. clouds (Contreras+ 2016)J/A+A/592/A21 : Are infrared dark clouds really quiescent? (Feng+, 2016)J/MNRAS/461/2288 : Infall motions in massive star-forming regions (He+, 2016)J/other/PASA/33.30 : MALT90 Catalogue (Rathborne+, 2016)J/ApJS/227/25 : 6 & 1.3cm deep VLA obs. toward high-mass SFRs (Rosero+, 2016)J/ApJ/824/29 : ATLASGAL clumps with IRAS & MALT90 data (Stephens+, 2016)J/A+A/599/A139 : ATLASGAL massive clumps dust characterization (Koenig+, 2017)J/A+A/600/L10 : Massive cluster progenitors from ATLASGAL (Csengeri+, 2017)J/AJ/154/140 : MALT90 kinematic dist. to molecular clumps (Whitaker+, 2017)J/A+A/617/A89 : G328.2551-0.5321 ALMA images (Csengeri+, 2018)J/A+A/615/A94 : ALMA massive protocluster gas clumps maps (Fontani+, 2018)J/ApJS/237/27 : Radio Ammonia Mid-plane Survey pilot survey (Hogge+, 2018)J/ApJ/867/94 : ALMA 1.3mm continuum flux data of C1-S core (Kong+, 2018)J/ApJ/862/105 : Core mass function across Gal. env. II. (Liu+, 2018)J/ApJS/243/13 : Massive star-forming clump from MALT90 (Li+, 2019)J/A+A/622/A99 : Starless MDCs of NGC6334 molecular spectra (Louvet+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/886/102https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/886/102http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/886/102https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/886/102https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/886/102http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/886/102GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/886/102/clumps (Physical properties of the prestellar, high-mass clump candidates (Table 1) and overall properties per clump of the embedded ALMA cores (Table 5))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/886/102/clumps?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/886/102/clumps?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/886/102/clumps?GETtext/xml+votable180.050000true272.5277083-19.46408330.005555555555555556Cone search capability for table J/ApJ/886/102/cores (Core parameters obtained from dendrograms (Table 3) and calculated properties (Table 4))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/886/102/cores?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/886/102/cores?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/886/102/cores?GETtext/xml+votable180.050000true272.528-19.46291670.0055555555555555566/29097 29115 30256 41814 42170 42172 42207 42226 42379 42392https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/886/102?format=asciiInfraredMillimeterdefaultJ/ApJ/886/102/clumpsPhysical properties of the prestellar, high-mass clump candidates (Table 1) and overall properties per clump of the embedded ALMA cores (Table 5)RefReference (4)meta.ref;pos.framecharAGALIRDC clump designation (GLLL.lll+BB.bbb) (1)meta.id;meta.maincharprimaryRAJ2000Hour of right ascension (J2000) (2)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000) (2)pos.eq.dec;meta.mainVlsr[-87.8/80] LSR velocity of the gaskm/sphys.veloc;pos.lsrfloatsigma[0.56/3.04] Velocity dispersion (3)km/sphys.veloc.dispersionfloatDist[2.9/5.4] Distance used for clump selectionkpcpos.distancefloatTdust[10.3/15] Dust temperature used for clump selectionKphys.temperaturefloatMset[580/5200] Mass used for clump selectionsolMassphys.massintRcl-pc[0.36/0.74] Clump radius in pc (5)pcphys.size.radiusfloatRcl[19/37] Clump radius in arcsec (5)arcsecphys.angSize;srcintMcl[520/3120] Clump mass (6)solMassphys.massintSigcl[0.1/1.1] Clump surface density ({Sigma}_cl_=M_cl_/{pi}R_cl_^2^)g.cm**-2phot.flux.density.sbfloatVol[0.9/13] Volume density (7)10000cm**-3phys.densityfloatSens[0.03/0.2] 1{sigma} mass sensitivitysolMassphys.mass;instr.sensitivityfloatNc[13/39] Number of coresmeta.numberintb_Mass[0.1/1.5] Minimum core masssolMassphys.mass;stat.minfloatB_Mass[2.7/30.4] Maximum core masssolMassphys.mass;stat.maxfloatMass[0.87/5] Mean masssolMassphys.mass;stat.meanfloatRad[1810/4810] Mean radiusauphys.size.radiusintnH2[0.6/9] Mean number density (n(H_2_))1e+06cm**-3meta.idfloatSig[0.18/1.7] Mean surface density ({Sigma})g.cm**-2phot.flux.density.sb;stat.meanfloatNH2pk[2.1/16.4] Mean peak column density (N_peak_(H_2_))1e+22cm**-2phys.columnDensity;stat.max;stat.meanfloatNpreNumber of prestellar coresmeta.numberintNproNumber of protostellar coresmeta.numberintSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJ/ApJ/886/102/coresCore parameters obtained from dendrograms (Table 3) and calculated properties (Table 4)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000[15/18] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[4/54] Degree of Declination (J2000)pos.eq.dec;meta.mainF224GHz[0.2/14.8] Peak Flux; primary beam correctedmJy/beamphot.flux.density;em.mm.200-400GHzfloatS224GHz[0.2/52.8] Integrated Flux; primary beam correctedmJyphot.flux.density;em.mm.200-400GHzfloatRad[0.27/2.46] Radius in arcsecarcsecphys.angSize;srcfloatCl[0/3]? Core Classification (1)meta.codeintnullableEdge[0/1] Core at edge of images are not used for analysis (G1)meta.codeintMass[0.12/30.4] Core MasssolMassphys.massfloatRadius[900/9670] Core calculated radius in auAUphys.size.radiusintnH2[0.2/26.2] Core Volume Density1e+06cm**-3phys.densityfloatSigma[0.08/4.78] Core Surface Densityg.cm**-2phot.flux.density.sbfloatNH2pk[0.12/9.52] Peak Column Density1e+23cm**-2phys.columnDensity;stat.maxfloatCoreALMA Core Name (ALMANN within Clump or EdgeN: see Note G1)meta.id;meta.maincharAGALIRDC Clump Namemeta.id.parentcharSimbadSimbad column added by the CDSmeta.ref.urlchar