J/AJ/170/239ivo://CDS.VizieR/J/AJ/170/239CDSZhou X.Yang JiSun Y.Yan Q.-Z.Yuan L.Su Y.Chen X.Zhang S.2026-07-23T12:18:01Z2026-07-23T13:15:08ZCDS support team

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

cds-question@unistra.frmolecular-cloudsinterstellar-mediumradio-astronomymilky-way-galaxymillimeter-astronomysubmillimeter-astronomyco-line-emissiongalaxy-kinematicsradio-spectroscopyMolecular clouds (MCs) are cradles of star and planet formation, thereby playing an important role in the evolution of galaxies. Based on the unbiased Milky Way Imaging Scroll Painting survey data of ^12^CO, ^13^CO, and C^18^O (J=1-0) line emission in two regions toward the inner and outer Galaxy, i.e., the G50 (44.75{deg}<=l<=60.25{deg}) and G120 (119.75{deg}<=l<=130.25{deg}) regions, the distribution of molecular gas is studied. Both regions have Galactic latitudes of |b|<=5.25{deg}. A catalog containing 24,724 MCs is constructed from the data. In our proximity, several molecular structures with large angular scales and small velocity dispersions are discovered, resembling curtains of mist. Beyond the nearby molecular gas, a clear aggregation of MCs along coherent structures in the Galactic plane is visible, sketching spiral arm structures. Nevertheless, the aggregation of MCs is also detected in the inter-arm region between the Perseus and Outer arms in the G50 region. The Galactic molecular disk in this inter-arm region is found to be thinner than that in the adjacent spiral arm region. In addition, the thickness of the Galactic molecular disk examined here is found to be correlated with the warp of it, indicating their homologous origins. The molecular disk has a typical thickness of ~220pc in the inner Galaxy. Moreover, the dispersion of the MC systemic velocity decreases with increasing galactocentric radius, resulting in lower kinematic distance uncertainties at larger radii. However, the Perseus arm segment in the G120 region exhibits a relatively large cloud-to-cloud velocity dispersion and split components in its MC velocity distribution.2025AJ....170..239Zhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/170/239CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/7A : Lynds' Catalogue of Dark Nebulae (LDN) (Lynds 1962)VII/114 : Massachusetts-Stony Brook Galactic Plane CO Survey (Clemens+ 1986)J/A+AS/25/25 : HII regions of the Northern Milky Way (Dubout-Crillon+ 1976)J/A+A/275/67 : Velocity Field of the outer Galaxy (Brand+ 1993)J/ApJ/551/852 : FCRAO CO survey of the outer Galaxy (Heyer+, 2001)J/A+A/383/631 : Catalogue of dust clouds in the Galaxy (Dutra+, 2002)J/A+A/487/993 : MAMBO Mapping of c2d Clouds and Cores (Kauffmann+, 2008)J/ApJS/185/198 : The Cepheus flare observed with IRAC and MIPS (Kirk+, 2009)J/ApJS/182/131 : Molecular clouds and clumps in the GRS (Rathborne+, 2009)J/ApJ/699/1153 : Kinematic dist. to GRS molecular clouds (Roman-Duval+, 2009)J/ApJ/723/492 : Phys. properties of GRS molecular clouds (Roman-Duval+, 2010)J/ApJ/798/L27 : CO obs. of molecular clouds in the 2nd quadrant (Sun+, 2015)J/ApJ/828/59 : Molecular clouds in the Milky Way with CO obs. (Su+, 2016)J/A+A/594/A28 : Planck Cat. of Galactic cold clumps (PGCC) (Planck+, 2016)J/A+A/601/A124 : Clouds in SEDIGISM sci. demonstration field (Schuller+, 2017)J/ApJS/230/17 : CO obs. of MCs in the Extreme Outer Galaxy region (Sun+, 2017)J/other/NatAs/3.320 : Galactic classical Cepheids catalog (Chen+, 2019)J/MNRAS/483/4291 : Properties of JCMT CO(3-2) molecular clouds (Colombo+, 2019)J/ApJ/885/131 : ~200 high-mass SFR plx & proper motion with VLBI (Reid+, 2019)J/A+A/632/A58 : Physical properties of CHIMPS clumps (Rigby+, 2019)J/MNRAS/500/3027 : The SEDIGISM survey: molecular clouds (Duarte-Cabral+, 2021)J/MNRAS/500/3064 : The SEDIGISM survey: First Data Release (Schuller+, 2021)J/ApJ/910/131 : Molecular gas distribution from MWISP CO survey (Su+, 2021)J/ApJS/257/51 : Morphological classif. of MWISP ^12^CO mol. cl. (Yuan+, 2021)J/ApJS/261/37 : 13CO emission in MWISP 12CO molecular clouds (Yuan+, 2022)J/ApJS/262/5 : A CO survey of the entire northern sky (Dame+, 2022)J/A+A/663/A56 : SEDIGISM: Molecular Cloud morphology I. (Neralwar+, 2022)J/ApJS/268/61 : Associations between SNRs & molecular clouds (Zhou+, 2023)J/AJ/167/220 : 207 molecular clouds dist. measurements; MWISP (Zhang+, 2024)J/ApJS/275/35 : CO molecular clouds from the MWISP project (Sun+, 2024)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/170/239https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/170/239http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/170/239https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/170/239https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/170/239http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/170/239GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/170/239/table2 (Basic parameters derived by 12CO (J=1-0) emission for all MCs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/170/239/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/170/239/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/170/239/table2?GETtext/xml+votable180.050000true12.1540766.220190.0055555555555555564/189 226-227 232-233 810 896 1916 1918-1919 2005 5/735 755 764-765 920-922 936-937 940 3234 3238 3244 3246 3588 3590 3592-3593 7653 7655 7661 7663 7670-7671 8004-8005 8016-8017 8019 6/2911 2933-2935 2937-2939 3015 3017 3019 3040-3041 3044-3045 3047 3594-3595 3598-3599 3610-3611 3614 3692 3694 3752-3753 3756-3757 3776-3778 12941-12943 12958-12959 12980-12982 12988 12990 14356 14358 14384-14386 30525-30527 30568 30570-30571 30574 30619 30641 30643 30649-30651 30672 30674 30679 32029 32072-32073 32112-32113 32116-32117 32119https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/170/239?format=asciiMillimeterRadiodefaultJ/AJ/170/239/table2Basic parameters derived by 12CO (J=1-0) emission for all MCsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCloudCloud identifier, MWISP GLLL.lll+BBB.bbbmeta.id;meta.maincharFlag=Clouds with incomplete coverage (1)meta.code.errorcharGLON[44.75/130.25] Intensity-weighted mean Galactic longitude, 12CO(1-0) linedegpos.galactic.lonindexedGLAT[-5.25/5.25] Intensity-weighted mean Galactic latitude, 12CO(1-0) linedegpos.galactic.latindexedVsys[-110.1/96.9] Intensity-weighted mean LSR velocity (2)km/sphys.veloc;pos.lsrfloatsigma[0.31/3.6] Velocity dispersion (3)km/sphys.veloc.dispersionfloatW[0.27/22] Average integrated intensityK.km/sphot.flux.density;em.line.CO;stat.meanfloatA[0.8/165491.5] Angular area of the cloud, square arcminutesarcmin**2phys.angSizedoubleNH2[5.9e+19/4e+21] H2 column density (4)cm**-2phys.columnDensityfloatDist[0.2/19.2]? Kinematic distance (5)kpcpos.distancefloatnullableRgal[5.7/19.8]? Distance to the Galactic center (6)kpcpos.distance;pos.galactocentricfloatnullableZgal[-900/1300]? Height from the Galactic plane (7)pcpos.cartesian.z;pos.galacticdoublenullableRad[8.8e-3/260]? Cloud radius (8)pcphys.size.radiusdoublenullableMass[5.7e-3/2.3e7]? Cloud mass (9)solMassphys.massfloatnullable_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.raindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decindexed