J/ApJS/262/16ivo://CDS.VizieR/J/ApJS/262/16doi:10.26093/cds/vizier.22620016CDSMa Y.Wang H.Zhang M.Wang C.Zhang S.Liu Y.Li C.Zheng Y.,Yuan L.Yang Ji2022-12-12T13:28:47Z2022-12-06T09:33:00ZCDS support team

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

cds-question@unistra.frmolecular-cloudsinterstellar-mediumsurveysco-line-emissionmolecular-physicsmilky-way-galaxyWe have obtained column density maps for an unbiased sample of 120 molecular clouds in the third quadrant of the Milky Way midplane (b<=|5|{deg}) within the Galactic longitude range from 195{deg} to 225{deg}, using the high-sensitivity ^12^CO and ^13^CO (J=1-0) data from the Milky Way Imaging Scroll Painting (MWISP) project. The probability density functions of the molecular hydrogen column density of the clouds, N-pdfs, are fitted with both a lognormal (LN) function and a lognormal plus power-law (LN+PL) function. The molecular clouds are classified into three categories according to their shapes of N-pdfs, i.e., LN, LN+PL, and UN (unclear). About 72% of the molecular clouds fall into the LN category, while 18% and 10% fall into the LN+PL and UN categories, respectively. A PL scaling relation, {sigma}_s_{propto}N_H2_^0.44^, exists between the width of the N-pdf, {sigma}_s_, and the average column density, N_H2_, of the molecular clouds. However, {sigma}_s_ shows no correlation with the mass of the clouds. A correlation is found between the dispersion of normalized column density, {sigma}_N/<N>_, and the sonic Mach number, M, of molecular clouds. Overall, as predicted by numerical simulations, the N-pdfs of the molecular clouds with active star formation activity tend to have N-pdfs with PL high-density tails.2022ApJS..262...16Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/262/16CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/360 : Gaia DR2 x AllWISE catalogue (Marton+, 2019)VII/20 : Catalogue of HII Regions (Sharpless 1959)VII/284 : A Catalogue of Galactic Supernova Remnants (Green, 2019)J/ApJ/551/852 : FCRAO CO survey of the outer Galaxy (Heyer+, 2001)J/A+A/487/993 : MAMBO Mapping of c2d Clouds and Cores (Kauffmann+, 2008)J/A+A/560/A24 : IRAM 30m CO-observations in W43 (Carlhoff+, 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/578/A29 : Column density maps in 4 IRDCs (Schneider+, 2015)J/MNRAS/458/3479 : SVM selection of WISE YSO Candidates (Marton+, 2016)J/ApJ/834/57 : MW molecular clouds from ^12^CO (Miville-Deschenes+, 2017)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)J/ApJS/254/3 : CO obs. of molecular clouds in the MW midplane (Ma+, 2021)J/ApJS/257/51 : Morphologies of MWISP ^12^CO mol. Clouds (Yuan+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/262/16https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/262/16http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/262/16https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/262/16https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/262/16http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/262/16GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/262/16/table1 (Properties of the probability density functions of the molecular hydrogen column density (N-pdfs) and physical parameters of the molecular clouds)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/262/16/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/262/16/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/262/16/table1?GETtext/xml+votable180.050000true93.210180515.22589460.0055555555555555565/5418 5510 5941 6/21641-21644 21647 21650 21657 21664 21668-21669 21671 21676 21679 21684 21690 22020 22028 22031 22035 22038-22039 22045 22047 22067 22069-22070 22074-22075 22088 22106-22107 22113 22115 22117 22121-22122 22124 22137-22138 22140 22161 22164-22165 22167 22172 22197 22205 22209-22210 22212 22214-22218 22221-22222 22232-22233 22243 22245 22249 22252-22253 22256-22257 22262 22264 22267-22268 23625-23626 23632 23636 23638 23645-23646 23661 23668-23670 23672-23674 23676 23760 23763 23772 23849 23853 23936 23938https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/262/16?format=asciiRadiodefaultJ/ApJS/262/16/table1Properties of the probability density functions of the molecular hydrogen column density (N-pdfs) and physical parameters of the molecular cloudsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMWISPMWISP designation (GLLL.lll+BB.bbb+vvv.vv) (1)meta.id;meta.maincharFigFigure number; column added by CDSmeta.idchar_GlonPositions from MWISP names (longitude part)degpos.galactic.lon_GlatPositions from MWISP names (latitude part)degpos.galactic.lat_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.ranullableindexedDistDistance of the cloudkpcpos.distancecharmu[-1.74/0.65]? Fit parameter, {mu}, of the N-pdfs in Equations 5-6 (Section 3.2.1)stat.fit.paramfloatnullablesigS[0.58/2.63]? Fit parameter, {sigma}_S_, of the N-pdfs in Equations 5-6 (Section 3.2.1)stat.fit.paramfloatnullablebr[0.26/1.9]? Fit parameter, b_r_, of the N-pdfs in Equations 5-6 (Section 3.2.1)stat.fit.paramfloatnullablea[-7.97/-1.41]? Fit parameter, a, of the N-pdfs in Equations 5-6 (Section 3.2.1)stat.fit.paramfloatnullableNpix[163/77828] Pixel numbermeta.numberintTpk[7.3/41.1] Peak excitation temperatureKphys.atmol.excitation;stat.maxfloatNH2[2e+20/3.4e+21] Average column density (2)cm**-2phys.columnDensity;stat.meandoubleRad[0.35/26.1]? Radiuspcphys.size.radiusfloatnullableMass[0/50552]? LTE masssolMassphys.massintnullableSkew[-0.58/0.74] skewness of the N-pdfstat.fit.paramfloatKurt[-1.17/0.25] kurtosis of the N-pdfstat.fit.paramfloattau[0.17/0.52] ^13^CO optical depth of the cloudphys.absorption.opticalDepthfloatM[0.68/37.7] Mach number (3)phys.velocfloatNyso[0/1097] Number of associated YSOsmeta.numberintaVir[0.58/463]? Virial parameter (4)phys.mass;arith.ratiofloatnullableShapeCategory of the N-pdf (5)meta.codechar_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