J/MNRAS/496/4637ivo://CDS.VizieR/J/MNRAS/496/4637doi:10.26093/cds/vizier.74964637CDSChen B.Wang S.Hou L.Yang Y.Li Z.Zhao H.Jiang B.2025-05-22T20:16:08Z2023-10-13T14:50:24ZCDS support team

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

cds-question@unistra.frmolecular-cloudsinterstellar-mediumextinctionmilky-way-galaxyinfrared-astronomyDistance measurements to molecular clouds are essential and important. We present directly measured distances to 169 molecular clouds in the fourth quadrant of the Milky Way. Based on the near-infrared photometry from the Two Micron All Sky Survey and the Vista Variables in the Via Lactea Survey, we select red clump stars in the overlapping directions of the individual molecular clouds and infer the bin averaged extinction values and distances to these stars. We track the extinction versus distance profiles of the sightlines towards the clouds and fit them with Gaussian dust distribution models to find the distances to the clouds. We have obtained distances to 169 molecular clouds selected from Rice et al. (2016ApJ...822...52R). The clouds range in distances between 2 and 11kpc from the Sun. The typical internal uncertainties in the distances are less than 5 per cent and the systematic uncertainty is about 7 per cent. The catalogue presented in this work is one of the largest homogeneous catalogues of distant molecular clouds with the direct measurement of distances. Based on the catalogue, we have tested different spiral arm models from the literature.2020MNRAS.496.4637Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/496/4637CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)II/376 : VISTA Variable in the Via Lactea Survey (VVV) DR4.2 (Minniti+, 2023)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/496/4637https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/496/4637http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/496/4637https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/496/4637https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/496/4637http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/496/4637GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/496/4637/table1 (Distances of molecular clouds in the fourth Galactic quadrant)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/496/4637/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/496/4637/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/496/4637/table1?GETtext/xml+votable180.050000true178.031-62.30240.0055555555555555565/10419 10444 10599 6/37904 41594 41599 41631 41655 41659 41662 41670 41673-41675 41682-41683 41685 41688-41689 41696-41698 41704 41758 41765-41767 41772 41780 41799 41802-41803 41805-41807 41813-41816 42159 42170-42174 42203 42206-42207 42210-42211 42213-42216 42220 42224-42226 42228-42230 42374 42377-42379 42381-42383 42387 42390 42392-42394 42400 42405 42434 42440 42497-42502 42504 42513 43013 43017 43019 43022 43024 43026 43028 43042https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/496/4637?format=asciiInfrareddefaultJ/MNRAS/496/4637/table1Distances of molecular clouds in the fourth Galactic quadrant_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.raindexed_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.decindexedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGLONGalactic longitudedegpos.galactic.lonGLATGalactic latitudedegpos.galactic.latsigrAngular size of the molecular clouddegphys.angSizefloatd0Distance of the cloudkpcpos.distancefloate_d0Error on d0kpcstat.errorfloatdAKsTotal extinction contributed by the dust grains in the cloudmagphys.absorptionfloatRRadius of the cloudpcphys.size.radiusintM? Mass of the cloud1000solMassphys.massfloatnullablevLSRLocal Standard of Rest velocitykm/sphys.veloc;pos.lsrfloatdR16? Kinematic distance from Rice et al. (2016ApJ...822...52R)kpcpos.distancefloatnullable