J/ApJS/254/3ivo://CDS.VizieR/J/ApJS/254/3doi:10.26093/cds/vizier.22540003CDSMa Y.Wang H.Li C.Lin L.Sun Y.Yang J.2022-01-17T11:34:49Z2021-08-02T08:43:54ZCDS support team

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

cds-question@unistra.frmolecular-cloudsco-line-emissiongalaxy-kinematicsmilky-way-galaxyIn this work, we study the properties of molecular clouds in the second quadrant of the Milky Way Midplane, from l=104.75{deg} to l=119.75{deg}, and b=-5.25{deg} to b=5.25{deg}, using the ^12^CO, ^13^CO, and C^18^O J=1-0 emission line data from the Milky Way Imaging Scroll Painting project. We identify 857 and 300 clouds in the ^12^CO and ^13^CO spectral cubes, respectively, using the DENDROGRAM + SCIMES algorithms. The distances of the molecular clouds are estimated, and physical properties such as the mass, size, and surface densities of the clouds are tabulated. The molecular clouds in the Perseus Arm are about 30-50 times more massive, and 4-6 times larger than the clouds in the Local Arm. This result, however, is likely to be biased by distance selection effects. The surface densities of the clouds are enhanced in the Perseus Arm, with an average value of ~100M_{sun}_/pc^2^. Here. we select the 40 most extended (>0.35arcdeg^2^) molecular clouds from the ^12^CO catalog to build the H_2_ column density probability distribution function (N-PDF). Some 78% of the N-PDFs of the selected molecular clouds are well fitted with log-normal functions with only small deviations at high densities, corresponding to star-forming regions with scales of ~1-5pc in the Local Arm, and ~5-10pc in the Perseus Arm. About 18% of the selected molecular clouds have power-law N-PDFs at high densities. In these molecular clouds, the majority of the regions fitted with the power law correspond to molecular clumps at sizes of ~1pc, or filaments at widths of ~1pc.2021ApJS..254....3Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/254/3CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/20 : Catalogue of HII Regions (Sharpless 1959)VII/278 : A Catalogue of Galactic Supernova Remnants (Green 2017)J/ApJ/428/693 : Rosette Nebula & Maddalena Cloud structures (Williams+ 1994)J/ApJ/551/852 : FCRAO CO survey of the outer Galaxy (Heyer+, 2001)J/ApJ/641/389 : Millimetric observations of IRDC cores (Rathborne+, 2006)J/ApJ/699/1092 : Giant molecular clouds (SRBY) (Heyer+, 2009)J/ApJ/723/492 : GRS molecular clouds physical data (Roman-Duval+, 2010)J/MNRAS/416/1764 : H_2_O Southern Galactic Plane Survey (HOPS) (Walsh+, 2011)J/MNRAS/431/1752 : ATLASGAL 6.7GHz methanol masers (Urquhart+, 2013)J/ApJS/212/1 : The WISE catalog of Galactic HII regions (Anderson+, 2014)J/ApJ/783/130 : Parallaxes of high mass star forming regions (Reid+, 2014)J/A+A/575/A79 : SPIRE 250um maps of 4 molecular clouds (Schneider+, 2015)J/ApJ/798/L27 : CO obs. of molecular clouds in the 2nd quadrant (Sun+, 2015)J/ApJS/224/7 : CO obs. of the outer arm in the 2nd quadrant (Du+, 2016)J/ApJ/834/57 : MW molecular clouds from ^12^CO (Miville-Deschenes+, 2017)J/MNRAS/477/2220 : Larson relations in massive clumps (Traficante+, 2018)J/ApJ/878/44 : ^13^CO clumps toward the Cas A supernova remnant (Ma+, 2019)J/A+A/633/A147 : FQS. Galactic Plane CO survey (Benedettini+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/254/3https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/254/3http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/254/3https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/254/3https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/254/3http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/254/3GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/254/3/table2 (Properties of ^12^CO clouds)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/254/3/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/254/3/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/254/3/table2?GETtext/xml+votable180.050000true339.9627655.030510.005555555555555556Cone search capability for table J/ApJS/254/3/table3 (Properties of ^13^CO clouds)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/254/3/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/254/3/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/254/3/table3?GETtext/xml+votable180.050000true333.4545660.693070.0055555555555555564/893-895 977 980 5/751 762-763 766-767 938 3551 3559 3567 3569-3571 3916-3917 3924-3926 6/2991 2999 3002 3041-3043 3046-3047 3058-3059 3063 3756 3758 14188 14190-14191 14194 14198-14200 14202-14203 14233 14235 14259 14262-14263 14265-14267 14272-14273 15708-15709 15712-15714 15716-15717https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/254/3?format=asciiRadiodefaultJ/ApJS/254/3/table2Properties of ^12^CO cloudsaVir[0.4/345.2]? Virial parameter, {alpha}_vir_phys.mass;arith.ratiofloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMWISPMWISP project source identifier (G1)meta.id;meta.maincharGLON[104.76/119.8] Centroid Galactic Longitudedegpos.galactic.lonGLAT[-5.2/5.3] Centroid Galactic Latitudedegpos.galactic.latamaj[66/4721] Intensity-weighted major axis, {theta}_a_arcsecphys.angSizeintbmin[26/2279] Intensity-weighted minor axis, {theta}_b_arcsecphys.angSize;srcintPA[-179/179] Position Angledegpos.posAngintVLSR[-101.3/15.5] Local Standard of Rest velocitykm/sphys.veloc;pos.lsrfloatsigma[0.36/5.4] Velocity dispersion, {sigma}_v_km/sphys.veloc.dispersionfloatDist[0.19/9.6]? Heliocentric distancekpcpos.distancefloatnullableReff[0.06/38.5]? Effective Radiuspcphys.size.radiusfloatnullableNH2[2e+20/5.7e+21] Average column density, N_0_(H_2_)cm**-2phys.columnDensity;stat.meandoubleMass[0.3/1.11e+6]? X_CO_ masssolMassphys.massdoublenullableSigma[7.8/432]? Mass surface density, {Sigma}solMass.pc**-2phys.densityfloatnullablen[9/10166]? Number densitycm**-3meta.number;phys.densitydoublenullable_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.decnullableindexedJ/ApJS/254/3/table3Properties of ^13^CO cloudsMatchIdentifier of matched MWISP ^12^CO cloudsmeta.id.crosscharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMWISPMWISP project source identifier (G1)meta.id;meta.maincharGLON[104.79/119.7] Centroid Galactic Longitudedegpos.galactic.lonGLAT[-4.5/5.2] Centroid Galactic Latitudedegpos.galactic.latamaj[53/3138] Intensity-weighted major axis, {theta}_a_arcsecphys.angSizeintbmin[28/1225] Intensity-weighted minor axis, {theta}_b_arcsecphys.angSize;srcintPA[-179/178] Position Angledegpos.posAngintVLSR[-72/6.5] Local Standard of Rest velocitykm/sphys.veloc;pos.lsrfloatsigma[0.3/4.3] Velocity dispersion, {sigma}_v_km/sphys.veloc.dispersionfloatDist[0.2/6.2]? Heliocentric distancekpcpos.distancefloatnullableRad[0.12/20.9]? Effective Radiuspcphys.size.radiusfloatnullableTex[7.8/47]? Excitation temperatureKphys.atmol.excitationfloatnullableTau[0.2/1]? Optical depthphys.absorption.opticalDepthfloatnullableNH2[8.2e+19/6.3e+23]? Average column density, N_0_(H_2_)cm**-2phys.columnDensity;stat.meandoublenullableMass[1.1/1.6e+6]? LTE masssolMassphys.massdoublenullableSigma[12.4/1703.1]? Mass surface density, {Sigma}solMass.pc**-2phys.densityfloatnullablen[60/23307]? Number densitycm**-3meta.number;phys.densitydoublenullableaVir[0.1/99.4]? Virial parameter, {alpha}_vir_phys.mass;arith.ratiofloatnullable_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