J/A+A/633/A147ivo://CDS.VizieR/J/A+A/633/A147doi:10.26093/cds/vizier.36330147CDSBenedettini M.Molinari S.Baldeschi A.Beltran M.T.Brand J.,Cesaroni R.Elia D.Fontani F.Merello M.Olmi L.Pezzuto S.,Ryg K.L.J.Schisano E.Testi L.Traficante A.2022-09-02T08:30:32Z2020-01-23T08:26:58ZCDS support team

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

cds-question@unistra.frmolecular-cloudsmillimeter-astronomyphotometrysubmillimeter-astronomyWe present the Forgotten Quadrant Survey (FQS), an ESO large project that used the 12m antenna of the Arizona Radio Observatory to map the Galactic Plane in the range 220{deg}<l<240{deg}, and -2.5{deg}<b<0{deg}, both in ^12^CO(1-0), and ^13^CO(1-0), at a spectral resolution of 0.65km/s and 0.26km/s. We used the (1-0) transition of carbon monoxide to trace the molecular component of the interstellar medium. Our data set allows us to easily identify how the molecular dense gas is organised at different spatial scales: from the giant clouds with their denser filamentary networks, down to the clumps and cores that host the new-born stars and to obtain reliable estimates of their key physical parameters such as size and mass. We present the first release of the data of the FQS survey and discuss their quality. Spectra with 0.65km/s velocity channels have noise ranging from 0.8K to 1.3K for ^12^CO (1-0) and from 0.3K to 0.6K for ^13^CO (1-0). In this first paper, we used the ^12^CO (1-0) spectral cubes to produce a catalogue of 263 molecular clouds. The clouds are grouped in three main structures corresponding to the Local, Perseus, and Outer arms up to a distance of ~8.6kpc from the Sun. This is the first self-consistent statistical catalogue of molecular clouds of the outer Galaxy obtained with a subarcminute spatial resolution and therefore able to detect not only the classical giant molecular clouds, but also the small clouds and to resolve the cloud structure at the sub-parsec scale up to a distance of a few kiloparsec. We found two classes of objects: structures with sizes above a few parsecs that are typical molecular clouds and may be self-gravitating, and subparsec structures that cannot be in gravitational equilibrium and are likely transient or confined by external pressure. We used the ratio between the Herschel H2 column density and the integrated intensity of the CO lines to calculate the CO conversion factor and we found mean values of (3.3+/-1.4)x10^20^cm^-2^/(K.km/s) and (1.2+/-0.4)x10^21^cm^-2^/(K.km/s), for ^12^CO (1-0) and ^13^CO (1-0), respectively. FQS contributes to the general effort in producing a new generation of high-quality spectroscopic data for the Galactic Plane in the less studied third Galactic Quadrant, toward the outer Galaxy. FQS has produced a data-set of great legacy value, largely improving the data quality both in terms of sensitivity and spatial resolution over previous data sets.2020A&A...633A.147Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/633/A147CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-tohttp://fqs.iaps.inaf.it : FQS project public web pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/633/A147https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/633/A147http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/633/A147https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/633/A147https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/633/A147http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/633/A147GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/633/A147/table1 (Properties of the molecular cloud catalogue)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/633/A147/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/633/A147/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/633/A147/table1?GETtext/xml+votable180.050000true104.068134-7.1600720.0055555555555555565/5378 5411 5417 9983 6/20821 20823 20829-20831 21504 21506-21507 21637-21639 21643 21656 21658 21677 21679-21680 21690 22032 39898-39899 39921 39923-39924 39926-39927 39929 40618https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/633/A147?format=asciiMillimeterdefaultJ/A+A/633/A147/table1Properties of the molecular cloud cataloguerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIndex[1/263] Molecular cloud indexmeta.idintNameName of the molecular cloud: FQS-MCLLL.lll+B.bbb, with LLL.lll, +B.bbb the Galactic longitude and latitude of the cloud centroidmeta.id;meta.maincharGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.latmajorIntensity-weighted semi-major axisarcsecphys.angSize;srcfloatminorIntensity-weighted semi-minor axisarcsecphys.angSize;srcfloatPA[] Position angle w.r.t. the Galactic longitudedegpos.posAngfloatVlsrLSR mean velocitykm/sphys.veloc;pos.lsrfloatsigmaVelocity dispersionkm/sphys.veloc.dispersionfloatICO^12^CO (1-0) integrated intensity across the area of the cloudK.km/sphot.flux.densityfloatLCO^12^CO (1-0) total luminosityK.km.s**-1.pc**2phys.luminosity;em.radiodoubleDistKinematic heliocentric distancekpcpos.distancefloatRadEquivalent circular radiuspcphys.size.radiusfloatAreaAreapc**2phys.areafloatMassMasssolMassphys.massdoubleSigmaAverage surface densitysolMass.pc**-2phot.flux.density.sb;stat.meanfloatalphavirVirial parameterphys.mass;arith.ratiodoublenlNumber of dendrogram leavesmeta.numberintFlag1[0/1]? Flag (1)meta.code.errorintnullableSimbadSimbad column added by the CDSmeta.ref.urlchar_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.decnullableindexedFlag2[0/2]? Flag (2)meta.code.errorintnullable