J/A+A/680/A4ivo://CDS.VizieR/J/A+A/680/A4doi:10.26093/cds/vizier/bc-n8/leCDSQuerejeta M.Pety J.Schruba A.Leroy A. K.Herrera C. N.Chiang I-D.,Meidt S. E.Rosolowsky E.Schinnerer E.Schuster K.Sun J.,Herrmann K.A.Barnes A.T.Beslic I.Bigiel F.Cao Y.Chevance M.,Eibensteiner C.Emsellem E.Faesi C.M.Hughes A.Kim J.Klessen R.S.,Kreckel K.Kruijssen J.M.D.Liu D.Neumayer N.Pan H.-A.Saito T.,Sandstrom K.Teng Y.-S.Usero A.Williams T.G.Zakardjian A.2026-07-03T06:35:41Z2023-12-04T08:32:18ZCDS support team

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

cds-question@unistra.frgalaxiesmolecular-cloudsco-line-emissionradio-astronomyWe present a new wide-field 10.75x10.75arcmin^2^ (~11x11kpc^2^), high-resolution (theta=3.6"~60pc) NOEMA CO(1-0) survey of the very nearby (d=3.45Mpc) spiral galaxy IC 342. The survey spans out to about 1.5 effective radii and covers most of the region where molecular gas dominates the cold interstellar medium. We resolved the CO emission into >600 individual giant molecular clouds and associations. We assessed their properties and found that overall the clouds show approximate virial balance, with typical virial parameters of alpha_vir=1-2. The typical surface density and line width of molecular gas increase from the inter-arm region to the arm and bar region, and they reach their highest values in the inner kiloparsec of the galaxy (median Sigma_mol_~80, 140, 160, and 1100M_{sun}_/pc^2^, sigma_CO_~6.6, 7.6, 9.7, and 18.4km/s for inter-arm, arm, bar, and center clouds, respectively). Clouds in the central part of the galaxy show an enhanced line width relative to their surface densities and evidence of additional sources of dynamical broadening. All of these results agree well with studies of clouds in more distant galaxies at a similar physical resolution. Leveraging our measurements to estimate the density and gravitational free-fall time at 90pc resolution, averaged on 1.5kpc hexagonal apertures, we estimate a typical star formation efficiency per free-fall time of 0.45% with a 16-84% variation of 0.33-0.71% among such 1.5kpc regions. We speculate that bar-driven gas inflow could explain the large gas concentration in the central kiloparsec and the buildup of the massive nuclear star cluster. This wide-area CO map of the closest face-on massive spiral galaxy demonstrates the current mapping power of NOEMA and has many potential applications. The data and products are publicly available at the IRAM archive.2023A&A...680A...4Qhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/680/A4CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/680/A4https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/680/A4http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/680/A4https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/680/A4https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/680/A4http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/680/A4GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/680/A4/tablea2 (Catalog of giant molecular cloud (GMC) properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/680/A4/tablea2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/680/A4/tablea2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/680/A4/tablea2?GETtext/xml+votable180.050000true56.573668.02958190.005555555555555556Cone search capability for table J/A+A/680/A4/list (List of datacubes)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/680/A4/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/680/A4/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/680/A4/list?GETtext/xml+votable180.050000true56.7020168.096280.0055555555555555566/3506-3507https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/680/A4?format=asciiRadiodefaultJ/A+A/680/A4/tablea2Catalog of giant molecular cloud (GMC) propertiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCloudID[0/636] Number of giant molecular cloud (GMC) from CPROPSmeta.id;meta.mainintRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainVLSRVelocity (LSR)km/sphys.veloc;pos.lsrfloatR? Giant molecular cloud (GMC) radiuspcphys.size.radiusfloatnullablePAGiant molecular cloud (GMC) ellipse position angledegpos.posAnginte? Giant molecular cloud (GMC) ellipticitysrc.ellipticityfloatnullablesigmaVGiant molecular cloud (GMC) velocity dispersionkm/sphys.veloc.dispersionfloatMCOGiant molecular cloud (GMC) luminous mass1e+06solMassphys.massfloatMvir? Giant molecular cloud (GMC) virial mass1e+06solMassphys.massfloatnullableJ/A+A/680/A4/tablea3Free-fall and depletion time measurementsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[1/61] Aperture numbermeta.id;meta.mainintRadiusGalactocentric radiuskpcphys.angSize;srcfloattau-ffFree-fall timeMyrtime.epochfloatSigma-molMolecular gas surface densitysolMass.pc**-2phot.flux.density.sbdoubleSigma-SFRStar formation rate surface densitysolMass.Myr**-1.pc**-2phys.SFRdoubletau-depDepletion timeMyrtime.epochfloatJ/A+A/680/A4/listList of datacubesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension of center (J2000)degpos.eq.ra;meta.mainNxNumber of pixels along X-axismeta.numberintDEJ2000Declination of center (J2000)degpos.eq.dec;meta.mainNyNumber of pixels along Y-axismeta.numberintNzNumber of slicesmeta.numberintbVRADLower value of VRAD intervalkm/sphys.veloc;pos.heliocentricintBVRADUpper value of VRAD intervalkm/sphys.veloc;pos.heliocentricintdVRADVRAD resolutionkm/spos.angResolutionintsizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitschar