J/A+A/574/A127ivo://CDS.VizieR/J/A+A/574/A127doi:10.26093/cds/vizier.35740127CDSKazandjian M.V.Meijerink R.Pelupessy I.Israel F.P.Spaans M.2015-07-11T19:08:01Z2015-02-05T08:56:59ZCDS support team

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

cds-question@unistra.frastronomical-modelsgalaxiesinfrared-sourcesinterstellar-mediummolecular-cloudsCO observations in active galactic nuclei and starbursts reveal high kinetic temperatures. Those environments are thought to be very turbulent due to dynamic phenomena, such as outflows and high supernova rates. We investigate the effect of mechanical heating on atomic fine-structure and molecular lines and on their ratios. We try to use those ratios as a diagnostic to constrain the amount of mechanical heating in an object and also study its significance on estimating the H_2_ mass. Equilibrium photodissociation models (PDRs hereafter) were used to compute the thermal and chemical balance for the clouds. The equilibria were solved for numerically using the optimized version of the Leiden PDR-XDR code. Large velocity-gradient calculations were done as post-processing on the output of the PDR models using RADEX. High-J CO line ratios are very sensitive to mechanical heating ({GAMMA}mech hereafter). Emission becomes at least one order of magnitude brighter in clouds with n~10^5^cm^-3^ and a star formation rate of 1M_{sun}/yr (corresponding to {GAMMA}mech=2x10^-19^erg/cm^3^/s). The Emission of low-J CO lines is not as sensitive to {GAMMA}mech, but they do become brighter in response to {GAMMA}mech. Generally, for all of the lines we considered, {GAMMA}mech increases excitation temperatures and decreases the optical depth at the line centre. Hence line ratios are also effected, strongly in some cases. Ratios involving HCN are a good diagnostic for {GAMMA}mech , where the HCN(1-0)/CO(1-0) increases from 0.06 to 0.25, and the HCN(1-0)/HCO^+^ (1-0) increase from 0.15 to 0.5 for amounts of {GAMMA}mech that are equivalent to 5% of the surface heating rate. Both ratios increase to more than 1 for higher {GAMMA}mech , as opposed to being much less than unity in pure PDRs. The first major conclusion is that low-J to high-J intensity ratios will yield a good estimate of the mechanical heating rate (as opposed to only low-J ratios). The second one is that the mechanical heating rate should be taken into account when determining AV or, equivalently, NH, and consequently the cloud mass. Ignoring {GAMMA}mech will also lead to large errors in density and radiation field estimates.2015A&A...574A.127Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/574/A127CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/574/A127https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/574/A127http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/574/A127https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/574/A127https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/574/A127http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/574/A127GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfrareddefaultJ/A+A/574/A127/crz1-0Models with varying cosmic ray ionization rate (see Fig. C6 in the appendix of the paper)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIndex[0/1955] Unique index of the modelmeta.idintngas[1/1.e6] Gas density of the PDR modelcm**-3phys.densitydoubleG0[1/1.e6] FUV incident flux (G1)1.6uW.m**-2stat.paramdoublegmechMechanical heating rate {Gamma}_mech_ (in erg/cm^3^/s, see paper)hW.m**-3stat.paramdoubleCR[5e-16/5e-13] Cosmic ray ionization rates**-1phot.count;em.X-raydoubleZ[1] Metallicity (solar metallicity)Sunphys.abund.ZfloatAv[5/30] Visual extinction of the cloudmagphys.absorption;em.opt.VfloatHCO+1-0? Flux of HCO+(1-0) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+2-1? Flux of HCO+(2-1) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+3-2? Flux of HCO+(3-2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+4-3? Flux of HCO+(4-3) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+5-4? Flux of HCO+(5-4) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+6-5? Flux of HCO+(6-5) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+7-6? Flux of HCO+(7-6) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+8-7? Flux of HCO+(8-7) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+9-8? Flux of HCO+(9-8) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN1-0? Flux of HCN(1-0) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN2-1? Flux of HCN(2-1) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN3-2? Flux of HCN(3-2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN4-3? Flux of HCN(4-3) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN5-4? Flux of HCN(5-4) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN6-5? Flux of HCN(6-5) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN7-6? Flux of HCN(7-6) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN8-7? Flux of HCN(8-7) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN9-8? Flux of HCN(9-8) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC1-0? Flux of HNC(1-0) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC2-1? Flux of HNC(2-1) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC3-2? Flux of HNC(3-2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC4-3? Flux of HNC(4-3) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC5-4? Flux of HNC(5-4) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC6-5? Flux of HNC(6-5) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC7-6? Flux of HNC(7-6) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC8-7? Flux of HNC(8-7) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC9-8? Flux of HNC(9-8) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableN(CO)? Column density of CO of the PDRcm**-2phys.columnDensitydoublenullableN(H2)? Column density of H_2_ of the PDRcm**-2phys.columnDensitydoublenullableJ/A+A/574/A127/gmzModels with varying mechanical heating rate and metallicities Z/Z_{sun}_ = 0.1, 0.5, 1.0, 2.0n_CO1-0[i] i for +{infinity}meta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintZ0[0.1/2.0] Initial metallicity (0.1, 0.5, 1.0, 2.0)Sunphys.abund.ZfloatIndex[0/4400] Unique index of the model within the initial metallicity Z0meta.idintngas[1/1.e6] Gas density of the PDR modelcm**-3phys.densitydoubleG0[1/1.e6] FUV incident flux (G1)1.6uW.m**-2stat.paramdoublegmechMechanical heating rate {Gamma}_mech_ (in erg/cm^3^/s, see paper)hW.m**-3stat.paramdoublealpha[0/1] Mechanical heating rate in terms of the surface heating (see eq-1 in the paper)stat.paramfloatZ[0.1/2] Metallicity (in solar metallicity)Sunphys.abund.ZfloatAv[5/30] Visual extinction of the cloudmagphys.absorption;em.opt.VfloatCO1-0? Flux of CO(1-0) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO2-1? Flux of CO(2-1) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO3-2? Flux of CO(3-2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO4-3? Flux of CO(4-3) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO5-4? Flux of CO(5-4) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO6-5? Flux of CO(6-5) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO7-6? Flux of CO(7-6) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO8-7? Flux of CO(8-7) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO9-8? Flux of CO(9-8) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO10-9? Flux of CO(10-9) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO11-10? Flux of CO(11-10) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO12-11? Flux of CO(12-11) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO13-12? Flux of CO(13-12) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO14-13? Flux of CO(14-13) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO15-14? Flux of CO(15-14) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCO16-15? Flux of CO(16-15) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO1-0? Flux of ^13^CO(1-0) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO2-1? Flux of ^13^CO(2-1) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO3-2? Flux of ^13^CO(3-2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO4-3? Flux of ^13^CO(4-3) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO5-4? Flux of ^13^CO(5-4) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO6-5? Flux of ^13^CO(6-5) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO7-6? Flux of ^13^CO(7-6) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO8-7? Flux of ^13^CO(8-7) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO9-8? Flux of ^13^CO(9-8) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO10-9? Flux of ^13^CO(10-9) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO11-10? Flux of ^13^CO(11-10) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO12-11? Flux of ^13^CO(12-11) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO13-12? Flux of ^13^CO(13-12) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO14-13? Flux of ^13^CO(14-13) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO15-14? Flux of ^13^CO(15-14) (erg/cm2/s)mW.m**-2phot.fluxdoublenullable13CO16-15? Flux of ^13^CO(16-15) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+1-0? Flux of HCO+(1-0) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+2-1? Flux of HCO+(2-1) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+3-2? Flux of HCO+(3-2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+4-3? Flux of HCO+(4-3) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+5-4? Flux of HCO+(5-4) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+6-5? Flux of HCO+(6-5) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+7-6? Flux of HCO+(7-6) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+8-7? Flux of HCO+(8-7) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCO+9-8? Flux of HCO+(9-8) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN1-0? Flux of HCN(1-0) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN2-1? Flux of HCN(2-1) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN3-2? Flux of HCN(3-2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN4-3? Flux of HCN(4-3) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN5-4? Flux of HCN(5-4) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN6-5? Flux of HCN(6-5) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN7-6? Flux of HCN(7-6) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN8-7? Flux of HCN(8-7) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHCN9-8? Flux of HCN(9-8) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC1-0? Flux of HNC(1-0) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC2-1? Flux of HNC(2-1) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC3-2? Flux of HNC(3-2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC4-3? Flux of HNC(4-3) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC5-4? Flux of HNC(5-4) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC6-5? Flux of HNC(6-5) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC7-6? Flux of HNC(7-6) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC8-7? Flux of HNC(8-7) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableHNC9-8? Flux of HNC(9-8) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCS1-0? Flux of CS(1-0) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCS2-1? Flux of CS(2-1) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCS3-2? Flux of CS(3-2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCS4-3? Flux of CS(4-3) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCN1-0? Flux of CN(1_1/2-0_1/2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableCN2-1? Flux of CN(2_3/2-1_3/2) (erg/cm2/s)mW.m**-2phot.fluxdoublenullableC609? Flux of [CI]609um (erg/cm2/s)mW.m**-2phot.fluxdoublenullableC369? Flux of [CI]369um (erg/cm2/s)mW.m**-2phot.fluxdoublenullableO63? Flux of [OI]63um (erg/cm2/s)mW.m**-2phot.fluxdoublenullableC+158? Flux of [CII]158.3um (erg/cm2/s)mW.m**-2phot.fluxdoublenullableN(CO)? Column density of CO of the PDRcm**-2phys.columnDensitydoublenullableN(H2)? Column density of H_2_ of the PDRcm**-2phys.columnDensitydoublenullableHeatTot? Integrated total heating up to the Av of the modelmW.m**-2stat.paramdoublenullableTkin[10/16260]? Weighted kinetic temperature used by Radex to compute the emission (see paper)Kspect.line.intensitydoublenullable