J/A+A/654/A144ivo://CDS.VizieR/J/A+A/654/A144doi:10.26093/cds/vizier.36540144CDSBenedettini M.Traficante A.Olmi L.Pezzuto S.Baldeschi A.,Molinari S.Elia D.Schisano E.Merello M.Fontani F.Rygl K.L.J.,Brand J.Beltran M.T.Cesaroni R.Liu S.J.Testi L.2022-01-19T13:09:18Z2021-10-22T12:34:19ZCDS support team

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

cds-question@unistra.frmolecular-cloudsmillimeter-astronomyphotometrysubmillimeter-astronomyNew-generation spectroscopic surveys of the Milky Way plane have been revealing the structure of the interstellar medium, allowing the simultaneous study of dense structures from single star-forming objects or systems to entire spiral arms. The good sensitivity of the new surveys and the development of dedicated algorithms now enable building extensive catalogues of molecular clouds and deriving good estimates of their physical properties. This allows studying the behaviour of these properties across the Galaxy. We present the catalogue of molecular clouds extracted from the ^13^CO (1-0) data cubes of the Forgotten Quadrant Survey, which mapped the Galactic plane in the range 220{deg}<l<240{deg}, and -2.5{deg}<b<0{deg} in ^12^CO (1-0) and ^13^CO (1-0). We compared the properties of the clouds of our catalogue with those of other catalogues. The catalogue contains 87 molecular clouds for which the main physical parameters such as area, mass, distance, velocity dispersion, and virial parameter were derived. These structures are overall less extended and less massive than the molecular clouds identified in the ^12^CO (1-0) data-set because they trace the brightest and densest part of the ^12^CO (1-0) clouds. Conversely, the distribution of aspect ratio, equivalent spherical radius, velocity dispersion, and virial parameter in the two catalogues are similar. The mean value of the mass surface density of molecular clouds is 87+/-55M_{sun}_/pc^2^ and is almost constant across the galactocentric radius, indicating that this parameter, which is a proxy of star formation, is mostly affected by local conditions. In data of the Forgotten Quadrant Survey, we find a good agreement between the total mass and velocity dispersion of the clouds derived from ^12^CO (1-0) and ^13^CO (1-0). This is likely because in the surveyed portion of the Galactic plane, the H_2_ column density is not particularly high, leading to a CO emission with a not very high optical depth. This mitigates the effects of the different line opacities between the two tracers on the derived physical parameters. This is a common feature in the outer Galaxy, but our result cannot be readily generalised to the entire Milky Way because regions with higher particle density could show a different behaviour.2021A&A...654A.144Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/654/A144CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-tohttp://fqs.iaps.inaf.it : Forgotten Quadrant Survey Home Pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/654/A144https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/654/A144http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/654/A144https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/654/A144https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/654/A144http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/654/A144GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/654/A144/tablea1 (Properties of the molecular cloud catalogue)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/654/A144/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/654/A144/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/654/A144/tablea1?GETtext/xml+votable180.050000true104.059641-7.1681950.0055555555555555565/5411 6/20828 20831 21504 21506 21513-21514 21638-21639 21643 21656 21669 21671 21677 21679-21680 21688 21690 22032 39899 39921 39923-39924 39926-39927 39929 39932 39934 40618https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/654/A144?format=asciiMillimeterdefaultJ/A+A/654/A144/tablea1Properties of the molecular cloud cataloguerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIndex[1/87] Molecular cloud indexmeta.idintNameName of the molecular cloud (1)meta.id;meta.maincharGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.latmajIntensity-weighted semi-major axisarcsecphys.angSize;srcfloatminIntensity-weighted semi-minor axisarcsecphys.angSize;srcfloatPA[] Position angle w.r.t. the Galactic longitudedegpos.posAngfloatVlsrMean velocitykm/sphys.veloc;stat.meanfloatsigmavVelocity dispersionkm/sphys.veloc.dispersionfloatICO^13^CO(1-0) integrated intensity across the area of the cloudK.km/sphot.flux.densityfloatdKinematic heliocentric distancekpcpos.distance;pos.heliocentricfloatREquivalent circular radiuspcphys.size.radiusfloatAAreapc**2phys.areafloatM13COMass from ^13^CO column densitysolMassphys.massdoubleM12COMass from X(^12^CO)solMassphys.massdoubleMH2Mass from Herschel H_2_ column densitysolMassphys.massdoubleSigmaAverage mass surface densitysolMass.pc**-2phys.density;stat.meanfloatalphavirVirial parameterphys.mass;arith.ratiofloatnlNumber of dendrogram leavesmeta.numberintflag1[0/1]? Flag (2)meta.code.errorintnullableflag2[0/2]? Flag (3)meta.code.errorintnullable_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