J/ApJ/953/164ivo://CDS.VizieR/J/ApJ/953/164doi:10.26093/cds/vizier/ba-xs-54CDSMuraoka K.Konishi A.Tokuda K.Kondo H.Miura R.E.Tosaki T.,Onodera S.Kuno N.Kobayashi M.I.N.Tsuge K.Sano H.Kitano N.,Fujita S.Nishimura A.Onishi T.Saigo K.Yamada R.I.Demachi F.,Tachihara K.Fukui Y.Kawamura A.2026-07-02T12:00:16Z2025-11-04T08:54:21ZCDS support team

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

cds-question@unistra.frgalaxieslocal-groupmolecular-cloudsco-line-emissiongalaxy-kinematicsWe present the results of ALMA-ACA 7m array observations in ^12^CO(J=2-1), ^13^CO(J=2-1), and C^18^O(J=2-1) line emission toward the molecular-gas disk in the Local Group spiral galaxy M33 at an angular resolution of 7.31"x6.50" (30x26pc). We combined the ACA 7m array 12CO(J=2-1) data with the IRAM 30m data to compensate for emission from diffuse molecular-gas components. The ACA+IRAM combined ^12^CO(J=2-1) map clearly depicts the cloud-scale molecular-gas structure over the M33 disk. Based on the ACA+IRAM ^12^CO(J=2-1) cube data, we cataloged 848 molecular clouds with a mass range from 10^3^-10^6^M_{sun}_. We found that high-mass clouds (>=10^5^M_{sun}_) tend to associate with the 8{mu}m bright sources in the spiral arm region, while low-mass clouds (<10^5^M_{sun}_) tend to be apart from such 8{mu}m bright sources and to exist in the inter-arm region. We compared the cataloged clouds with GMCs observed by the IRAM 30m telescope at 49pc resolution (IRAM GMC), and found that a small IRAM GMC is likely to be identified as a single molecular cloud even in ACA+IRAM CO data, while a large IRAM GMC can be resolved into multiple ACA+IRAM clouds. The velocity dispersion of a large IRAM GMC is mainly dominated by the line-of-sight velocity difference between small clouds inside the GMC rather than the internal cloud velocity broadening.2023ApJ...953..164Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/953/164CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/233 : 2MASS All-Sky Extended Source Catalog (XSC) (IPAC/UMass, 2003-2006)J/ApJS/149/343 : Giant molecular clouds in M33 (Engargiola+, 2003)J/ApJ/633/871 : Positions and photometry of HII knots in M51 (Calzetti+, 2005)J/AJ/131/2478 : M31 and M33 UBVRI photometry (Massey+, 2006)J/AJ/134/2474 : H{alpha} emission-line stars in 7 dwarfs gal. (Massey+, 2007)J/ApJ/661/830 : Giant molecular clouds of M33 (Rosolowsky+, 2007)J/ApJ/686/948 : CO in extragalactic giant molecular clouds (Bolatto+, 2008)J/ApJS/178/56 : CO observations of LMC Giant Molecular clouds (Fukui+, 2008)J/ApJ/703/517 : The Spitzer Local Volume Legacy: IR photometry (Dale+, 2009)J/ApJS/184/1 : Molecular clouds in the LMC by NANTEN. II. (Kawamura+, 2009)J/A+A/522/A3 : M33 CO(2-1) and HI integrated intensity maps (Gratier+, 2010)J/A+A/542/A108 : Giant molecular clouds in M33 (Gratier+, 2012)J/ApJ/761/37 : CO obs. in giant molecular clouds of M33 (Miura+, 2012)J/ApJ/784/3 : The PAWS catalogs of GMCs and islands in M51 (Colombo+, 2014)J/A+A/594/A28 : Planck Catalog of Galactic cold clumps (PGCC) (Planck+, 2016)J/A+A/601/A146 : M33 molecular clouds & young clusters (Corbelli+, 2017)J/ApJ/834/57 : MW molecular clouds from ^12^CO (Miville-Deschenes+, 2017)J/ApJS/257/43 : PHANGS-ALMA: CO(2-1) imaging of galaxies (Leroy+, 2021)J/ApJ/927/149 : Low-J CO line ratios for 152 CO map pairs (Leroy+, 2022)J/ApJ/949/63 : CO survey toward SMC north with ACA. II. (Ohno+, 2023)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/953/164https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/953/164http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/953/164https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/953/164https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/953/164http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/953/164GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/953/164/table3 (List of cataloged molecular clouds)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/953/164/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/953/164/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/953/164/table3?GETtext/xml+votable180.050000true23.4641530.657440.0055555555555555566/2154-2155https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/953/164?format=asciiRadiodefaultJ/ApJ/953/164/table3List of cataloged molecular cloudsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/848] Cloud identifier numbermeta.id;meta.mainintRAJ2000[23.32/23.7] Right Ascension (J2000) (1)degpos.eq.ra;meta.mainDEJ2000[30.49/31] Declination (J2000) (1)degpos.eq.dec;meta.mainRgal[0.07/5.6] Galactocentric radius (2)kpcphys.size.radius;pos.galactocentricfloatVLSR[-267/-101] Local Standard of Rest radial velocitykm/sspect.dopplerVeloc;pos.lsrintRad[6.8/71.6] Deconvolved radiuspcphys.size.radiusfloate_Rad[1.9/19] Uncertainty in Radpcstat.error;phys.size.radiusfloatsigmav[1/6.1] Deconvolved velocity dispersionkm/sphys.veloc.dispersionfloate_sigmav[0.2/2.5] Uncertainty in sigmavkm/sstat.error;phys.veloc.dispersionfloatMCO[0.7/264.3] Luminosity mass from ^12^CO(J=2-1) flux10000solMassphys.mass;em.line.COfloate_MCO[0.1/13.3] Uncertainty in MCO10000solMassstat.error;phys.mass;em.line.COfloatMVir[1/185.4] Mass inferred from virial theorem10000solMassphys.massfloate_MVir[1/53.1] Uncertainty in MVir10000solMassstat.error;phys.massfloatI12CO[0.5/45.8] The ^12^CO(J=2-1) intensity (1)K.km/sspect.line.intensity;em.line.COfloate_I12CO[0.04/0.3] Uncertainty in I12COK.km/sstat.error;spect.line.intensity;em.line.COfloatS/N[6/139.5] Signal-to-Noise ratio of ^12^CO(J=2-1) brightness temperature (1)stat.snrfloatl_I13COThe 3{sigma} limit flag on I13COmeta.code.errorcharSimbadSimbad column added by the CDSmeta.ref.urlcharI13CO[0.14/7.4] The ^13^CO(J=2-1) intensity (1)K.km/sspect.line.intensity;em.line.COfloate_I13CO[0.04/0.2]? Uncertainty in I13COK.km/sstat.error;spect.line.intensity;em.line.COfloatnullablel_R13/12The 3{sigma} limit flag on R13/12meta.code.errorcharR13/12[0.03/0.41] Intensity ratio of ^13^CO(J=2-1) to ^12^CO (J=2-1) (1)spect.line.intensity;arith.ratio;em.line.COfloate_R13/12[0/0.05]? Uncertainty in R13/12stat.error;spect.line.intensity;arith.ratiofloatnullablePA[-90/90] Position angle of major axis, {phi} (3)degpos.posAngintb/a[1/15] Ratio between major and minor axes (4)phys.angSize;arith.ratiofloatIRAM[23/550]? GMC counterpart identified with IRAM 30m telescope (5)meta.id.crossintnullable