J/ApJS/257/51ivo://CDS.VizieR/J/ApJS/257/51doi:10.26093/cds/vizier.22570051CDSYuan L.Yang J.Du F.Liu X.Zhang S.Lin Z.Sun J.Yan Q.-Z.,Ma Y.Su Y.Sun Y.Zhou X.2022-06-13T13:25:26Z2022-04-08T10:10:33ZCDS support team

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

cds-question@unistra.frmolecular-cloudsco-line-emissiongalaxy-classification-systemsinterstellar-mediummilky-way-galaxysurveysWe attempt to visually classify the morphologies of 18190 molecular clouds, which are identified in the ^12^CO(1-0) spectral line data over ~450deg^2^ of the second Galactic quadrant from the Milky Way Imaging Scroll Painting project. Using the velocity-integrated intensity maps of the ^12^CO(1-0) emission, molecular clouds are first divided into unresolved and resolved ones. The resolved clouds are further classified as nonfilaments or filaments. Among the 18190 molecular clouds, ~25% are unresolved, ~64% are nonfilaments, and ~11% are filaments. In the terms of the integrated flux of ^12^CO(1-0) spectra of all 18190 molecular clouds, ~90% are from filaments, ~9% are from nonfilaments, and the remaining ~1% are from unresolved sources. Although nonfilaments are dominant in the number of the discrete molecular clouds, filaments are the main contributor of ^12^CO emission flux. We also present the number distributions of the physical parameters of the molecular clouds in our catalog, including their angular sizes, velocity spans, peak intensities of ^12^CO(1-0) emission, and ^12^CO(1-0) total fluxes. We find that there is a systematic difference between the angular sizes of the nonfilaments and filaments, with the filaments tending to have larger angular scales. The H2 column densities of them are not significantly different. We also discuss the observational effects, such as those induced by the finite spatial resolution, beam dilution, and line-of-sight projection, on the morphological classification of molecular clouds in our sample.2021ApJS..257...51Yhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/257/51CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJS/196/18 : CO survey of galactic molecular clouds. II. (Bieging+, 2011)J/AJ/142/71 : Proper motions and phot. of stars near NGC7380 (Chen+, 2011)J/MNRAS/418/2121 : CO 3-2 observations of outflows in W5 (Ginsburg+, 2011)J/A+A/554/A55 : C^18^O(1-0) and N_2_H^+^(1-0) in L1495/B213 (Hacar+, 2013)J/A+A/550/A83 : NIR observations of CG1 and CG2 (Makela+, 2013)J/ApJ/828/59 : Molecular clouds in the Milky Way with CO obs. (Su+, 2016)J/MNRAS/456/2041 : Fragmentation in filamentary mol. clouds (Contreras+ 2016)J/ApJS/224/7 : CO obs. of the outer arm in the 2nd quadrant (Du+, 2016)J/ApJS/230/17 : CO obs. of MCs in the Extreme Outer Galaxy (Sun+, 2017)J/ApJS/248/15 : CO obs. of mol. outflows in Cygnus complex (Zhang+, 2020)J/ApJS/254/3 : CO obs. of molecular clouds in the MW midplane (Ma+, 2021)http://www.radioast.nsdc.cn/mwisp.php : MWISP project home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/257/51https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/257/51http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/257/51https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/257/51https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/257/51http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/257/51GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/257/51/table1 (A catalog of molecular clouds)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/257/51/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/257/51/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/257/51/table1?GETtext/xml+votable180.050000true332.1469661.55350.0055555555555555563/223 4/189-191 197-199 204-206 225-228 232 977 980 5/443 446-447 490-491 735 751 785 787 805 807 813-815 828-830 832-834 840 842 897-899 916 920-922 932-934 936-938 3547 3549-3551 3557 3559 3565 3567 3916-3917 3924-3926 6/1767 1778-1779 1782-1783 1954-1955 1958-1959 1970 1976 1978 2933 2935 2937-2939 2991 2998-2999 3001-3003 3015 3021-3023 3127 3133-3135 3137 3139 3145-3147 3245-3247 3250-3251 3324-3326 3340-3342 3364 3366 3456-3458 3464 3466 3587 3668 3672-3674 3692 3696 3740-3742 3756-3758 3760-3762 3776-3778 14175 14186-14187 14194-14195 14225 14227 14233 14235 14257 14259 14265-14267 15708 15712-15714 15716-15717https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/257/51?format=asciiOpticalRadiodefaultJ/ApJS/257/51/table1A catalog of molecular cloudsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDIdentifier (GLLL.lll+BB.bbb-NNN.NN; with NNN.NN=VLSR)meta.id;meta.maincharGLON[104.7/150.3] Central Galactic longitude (1)degpos.galactic.lonindexedGLAT[-5.3/5.3] Central Galactic latitude (1)degpos.galactic.latindexedVLSR[-95/20] Central Local Standard of Rest velocity (2)km/sphys.veloc;pos.lsrfloatArea[1/60746] Angluar cloud area, projected along the line of sightarcmin**2phys.angSizedoubleVspan[0.5/43.42] Cloud cube velocity span (3)km/sphys.velocfloatPInt[1.2/50.8] Peak ^12^CO(1-0) line intensityKspect.line.intensity;stat.maxfloatFlux[0.5/390097] Integrated ^12^CO(1-0) flux (4)K.km.s**-1.arcmin**-2phot.flux.density;em.line.COdoubleMorphMorphology type (5)src.morph.typechar_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.ranullableindexed_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.decnullableindexed