J/ApJ/915/92ivo://CDS.VizieR/J/ApJ/915/92doi:10.26093/cds/vizier.19150092CDSTarantino E.Bolatto A.D.Herrera-Camus R.Harris A.I.Wolfire M.,Buchbender C.Croxall K.V.Dale D.A.Groves B.Levy R.C.Riquelme D.,Smith J.-DT.Stutzki J.2023-01-19T08:58:58Z2023-01-18T11:50:43ZCDS support team

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

cds-question@unistra.frgalaxiesinfrared-sourcesinterstellar-mediummolecular-physicschemical-abundancesThe [CII] fine-structure transition at 158{mu}m is frequently the brightest far-infrared line in galaxies. Due to its low ionization potential, C+ can trace the ionized, atomic, and molecular phases of the ISM. We present velocity-resolved [CII] and [NII] pointed observations from SOFIA/GREAT on ~500pc scales in the nearby galaxies M101 and NGC 6946 and investigate the multiphase origin of [CII] emission over a range of environments. We show that ionized gas makes a negligible contribution to the [CII] emission in these positions using [NII] observations. We spectrally decompose the [CII] emission into components associated with the molecular and atomic phases using existing CO (2-1) and HI data and show that a peak signal-to-noise ratio of 10-15 is necessary for a reliable decomposition. In general, we find that in our pointings >~50% of the [CII] emission arises from the atomic phase, with no strong dependence on star formation rate, metallicity, or galactocentric radius. We do find a difference between pointings in these two galaxies, where locations in NGC 6946 tend to have larger fractions of [CII] emission associated with the molecular phase than in M101. We also find a weak but consistent trend for fainter [CII] emission to exhibit a larger contribution from the atomic medium. We compute the thermal pressure of the cold neutral medium through the [CII] cooling function and find log(P_th_/k)=3.8-4.6[K/cm^3^], a value slightly higher than similar determinations, likely because our observations are biased toward star-forming regions.2021ApJ...915...92Thttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/915/92CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/432/369 : Leiden Atomic and Molecular Database (LAMDA) (Schoeier+, 2005)J/ApJS/178/247 : H{alpha} and [NII] survey in local 11 Mpc (Kennicutt+, 2008)J/A+A/486/629 : Effective collision strengths for C II (Tayal, 2008)J/AJ/136/2563 : HI Nearby Galaxy Survey, THINGS (Walter+, 2008)J/ApJ/703/1672 : Far-IR and H{alpha} fluxes in galaxies (Kennicutt+, 2009)J/ApJ/703/1569 : Radial distribution in SINGS gal. I. (Munoz-Mateos+, 2009)J/ApJ/734/65 : CI radial velocities with HST/STIS (Jenkins+, 2011)J/A+A/539/A143 : Nearby B-stars stellar param. and abundances (Nieva+, 2012)J/ApJ/774/73 : ALMA CO observations of 30 Dor (Indebetouw+, 2013)J/A+A/578/A53 : Spectroscopy of Herschel Dwarf Galaxy Survey (Cormier+, 2015)J/A+A/575/A9 : M17-SW datacubes in C and CO lines (Perez-Beaupuits+, 2015)J/A+A/586/A37 : M33 center and BCLMP302 [CII] spectroscopy (Mookerjea+, 2016)J/A+A/589/A28 : N66, N88 & N25+N26 emission line maps (Requena-Torres+, 2016)J/A+A/595/A34 : SOFIA Horsehead nebula region datacube (Risacher+, 2016)J/A+A/591/A33 : [CII]158um and [NII]205um IC 342 spectra (Roellig+, 2016)J/ApJ/845/96 : [CII] emission in the ISM of 20 nearby gal. (Croxall+, 2017)J/A+A/599/A9 : NGC 4214 [CII] line profile (Fahrion+, 2017)J/A+A/626/A23 : Herschel Dwarf Galaxy Survey PACS sp. (Cormier+, 2019)J/A+A/632/A106 : LMC-N11 (LHA 120-N11) [CII], HI, CO sp. (Lebouteiller+, 2019)J/A+A/621/A62 : 4 LMC SFRs velocity profile maps (Okada+, 2019)J/A+A/643/A141 : Tracing total molecular gas in galaxies (Madden+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/915/92https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/915/92http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/915/92https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/915/92https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/915/92http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/915/92GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/915/92/table1 ([CII] SOFIA/GREAT spectra summary)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/915/92/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/915/92/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/915/92/table1?GETtext/xml+votable180.050000true308.81916760.1825280.0055555555555555566/11434 15592-15593https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/915/92?format=asciiInfrareddefaultJ/ApJ/915/92/table1[CII] SOFIA/GREAT spectra summaryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalGalaxysrc.class.starGalaxycharRegRegion, in Galaxy (G1)meta.id;meta.maincharprimaryCycle[2/4] Cycleobs.proposal.cycleintRAJ2000[14/20] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[54/60] Degree of Declination (J2000)pos.eq.dec;meta.mainZ[7.9/8.7] Metal abundance, 12+log(O/H)phys.abund.ZfloatSFRD[-1.4e-5/0.7] Star formation rate densitysolMass.yr**-1.kpc**-2phys.SFRdoubleI[CII][-5.7/34.2] Integrated intensity, [CII] (1)K.km/sphot.flux.densityfloate_I[CII][0.4/4.6] Uncertainty in I[CII]K.km/sstat.errorfloatRMS[0.02/0.2] RMSKstat.errorfloatGDisplay the Gaussian fits summary (link to Table 2)meta.ref.urlintnullableSpDisplay the single spectrum decomposition (link to Table 4)meta.ref.urlintnullableJ/ApJ/915/92/table2[CII] Gaussian fits summaryGalGalaxysrc.class.starGalaxycharRegRegion, in Galaxy (G1)meta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAmp[0.06/1.2] Gaussian amplitude fitKsrc.var.amplitude;meta.modelledfloate_Amp[0.02/0.09] Uncertainty in AmpKstat.errorfloatvpeak[-54.4/322] Fitted peak velocitykm/sphys.veloc;stat.maxfloate_vpeak[0.5/6.2] Uncertainty in vpeakkm/sstat.errorfloatFWHM[9/51] Full width half maximum of the Gaussian fitkm/sspect.line.width;meta.modelledfloate_FWHM[1/15] Uncertainty in FWHMkm/sstat.error;phys.angSizefloatJ/ApJ/915/92/table3Results of the decompositionrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintPropertyPropertymeta.notecharSampleSub-sample region selection (1)meta.id;meta.datasetcharNsp[10/78] Number of spectra stackedmeta.numberintSNR-CII[10/24] Signal-to-noise, [CII]stat.snrfloatSFRD[0.7/20.1] Average weighted star formation rate density0.01solMass.yr**-1.kpc**-2phys.SFR;stat.meanfloatZ[8.4/8.62] Metal abundance, 12+log(O/H)phys.abund.Zfloatgc[0.2/0.7] Normalized galactocentric radius, R/R25phys.size.radius;arith.ratio;pos.galactocentricfloatSgas[23.6/58.4] Total gas surface densitysolMass.pc**-2phot.flux.density.sbfloatfCO[-0.03/0.7] Fraction of the integrated [CII] intensity associated with molecular gasspect.line.intensity;arith.ratiofloate_fCO[0.07/0.23] Uncertainty in fCOstat.errorfloatfHI[0.26/1.03] Fraction of the integrated [CII] intensity associated with atomic gasspect.line.intensity;arith.ratiofloate_fHI[0.07/0.26] Uncertainty in fHIstat.errorfloatchi2-2c[0.32/3.29] Reduced {chi}^2^ using both HI and COstat.fit.chi2floatchi2-1c[0.64/3.27] Reduced {chi}^2^ using CO or HI one-component modelstat.fit.chi2floatJ/ApJ/915/92/table4Single spectrum decompositiongc[0.3/0.9] Normalized galactocentric radius, R/R25phys.size.radius;pos.galactocentric;arith.ratiofloatRegRegion, in Galaxy (G1)meta.id;meta.maincharSgas[44/132] Total gas surface densitysolMass.pc**-2phot.flux.density.sbfloatfCO[0.39/0.53] Fraction of the integrated [CII] intensity associated with molecular gasspect.line.intensity;arith.ratiofloate_fCO[0.1/0.15] Uncertainty in fCOstat.errorfloatfHI[0.46/0.65] Fraction of the integrated [CII] intensity associated with atomic gasspect.line.intensity;arith.ratiofloate_fHI[0.08/0.14] Uncertainty in fHIstat.errorfloatchi2-2c[0.69/1.61] Reduced {chi}^2^ using both HI and COstat.fit.chi2floatchi2-1c[1.12/2.51] Reduced {chi}^2^ using CO or HI one-component modelstat.fit.chi2floatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalGalaxysrc.class.starGalaxycharCycle[2/4] Cycleobs.proposal.cycleintSNR-CII[9/15] Signal-to-noise, [CII]stat.snrfloatSFRD[4.8/69] Average weighted star formation rate density0.01solMass.yr**-1.kpc**-2phys.SFR;stat.meanfloatZ[8.4/8.5] Metal abundance, 12+log(O/H)phys.abund.Zfloat