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The Greenhouse Effect in Buried Galactic Nuclei and the Resonant HCN Vibrational Emission

T0 review · 3 major / 4 minor · reviewed 2026-08-14 · deepseek-v4-flash

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Pith's one-line read When hydrogen columns in buried galactic nuclei exceed about $10^{25}$ cm$^{-2}$, infrared photons are trapped so efficiently that the inner dust heats strongly and the HCN bending-mode lines become optically thick, explaining observed…

desk verdict A credible quantitative case for greenhouse-driven HCN vibrational emission in buried nuclei, with an honest and accurate statement of the spherical-symmetry limit that should be tested with 3D models. read the letter →

arxiv 1908.04058 v1 pith:S3M6BCWM submitted 2019-08-12 astro-ph.GA

Eduardo González-Alfonso , Kazushi Sakamoto This is my paper · ORCID
classification astro-ph.GA
keywords buriedgalacticnucleiHCNvibrationalemissiondustradiativetrappinggreenhouseeffectinfraredluminousgalaxiesactivestarbursttransfer
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

This paper argues that the bright vibrational lines of HCN seen toward buried galactic nuclei are a direct consequence of a greenhouse effect in the dust: when the hydrogen column density exceeds roughly $10^{25}$ cm$^{-2}$, infrared photons emitted by dust cannot escape, so they heat the inner regions far above the temperature expected from the luminosity alone. The trapped light boosts the mid-infrared intensity by more than an order of magnitude, populating the $\nu_2=1$ bending state of HCN and making the $J=3-2$ and $4-3$ vibrational lines optically thick. The authors show that a single set of parameters—HCN abundance near $10^{-6}$ relative to H$_2$ and surface brightness $\Sigma_{\rm IR}\sim (0.5-2)\times 10^8\ L_\odot\ {\rm pc}^{-2}$—reproduces the observed line fluxes in NGC 4418, Arp 220, IC 860, Zw 049.057, and Mrk 231, while also matching far-infrared photosphere temperatures and bright millimeter continuum. A sympathetic reading is that this is the first quantitative case that the same radiation trapping which heats the dust also powers the cyanopolyne vibrational emission, turning a qualitative idea into calibrated predictions.

What carries the argument

The load-bearing object is the dust-temperature profile obtained from a spherically symmetric continuum radiative-transfer calculation in which radiation is carried by parallel rays through a power-law density cocoon ($\rho\propto r^{-q}$, $q=1$ or 1.5), heating shells by local absorption and re-emission. A compact blackbody at 1300 K represents the AGN case; a distributed energy deposition proportional to the dust mass and density represents the starburst case. The greenhouse effect appears in the equilibrated $T_{\rm dust}(r)$: at high columns, inward (backwarming) fluxes almost cancel outward fluxes, so $\Upsilon_{\rm IR}=4\pi r^2\sigma T_{\rm dust}(r)^4$ is not conserved and the inner shells are far hotter than the optically thin solution. These temperatures are then fed into a model of HCN with 25 rotational levels in the ground vibrational state and up to 48 levels in the $\nu_2=1$ bending state, treating gas and dust as thermally coupled and including line–dust extinction and ro-vibrational overlaps. The single most important relation is that the HCN $\nu_2=1\ f\ J=3-2$ line is in LTE at the local dust temperature wherever the 14 $\mu$m continuum is optically thick, so the emergent line flux is set by the solid angle of the region where $T_{\rm dust}\approx 200$ K.

What would settle it

A spatially resolved map of the HCN $\nu_2=1$ $J=3-2$ line toward a nucleus with $N_{\rm H_2}\approx 10^{25}$ cm$^{-2}$ should show a central dip in line brightness (ring-like morphology), because the saturated line absorbs the bright 1.1 mm continuum; detecting a centrally peaked line instead would contradict the optically thick, greenhouse-driven picture.

Watch

Extended reading notes

Core claim

The central claim is that radiative trapping, not a hotter central engine, is what makes buried galactic nuclei appear to have warm interiors. In the models, once $N_{\rm H_2}\gtrsim 10^{25}$ cm$^{-2}$ the optical depth at 20 $\mu$m reaches hundreds, so any photon emitted in the inner shells is absorbed and re-emitted many times before it escapes. This backwarming raises the dust temperature in the inner third of the source to roughly 200–500 K, even when the externally observed spectral energy distribution looks cold, and raises the mean mid-infrared intensity inside the cocoon by more than a factor of ten. At those temperatures and columns, the HCN $\nu_2=1$ state is populated so efficiently that the $J=3-2$ and $4-3$ vibrational lines saturate ($\tau\gtrsim 1$) over a substantial fraction of the source, with flux ratios near the optically thick value $(\nu_{4-3}/\nu_{3-2})^2\approx 1.8$. The same greenhouse that traps the continuum therefore dictates the line luminosity, and the authors calibrate this to match the observed brightnesses in five galaxies with one fiducial abundance and a narrow range of surface brightness.

Load-bearing premise

The models assume smooth spherical symmetry with isotropic column densities and no clumping; the authors acknowledge this may overestimate the dust temperature, because in real systems radiation can escape along low-column sightlines and weaken the greenhouse heating.

Editorial extensions

If this is right

  • The HCN $\nu_2=1$ $J=3-2$ and $4-3$ lines should be optically thick in buried galactic nuclei with $N_{\rm H_2}\gtrsim 10^{25}$ cm$^{-2}$ and $\Sigma_{\rm IR}\gtrsim 10^7\ L_\odot$ pc$^{-2}$, with a flux ratio close to 1.8.
  • The same models predict bright, compact (sub)millimeter continuum with brightness temperatures of several hundred Kelvin, especially for AGN-heated cocoons, providing a way to spot buried active nuclei.
  • Far-infrared photosphere temperatures of 80–160 K emerge naturally from the greenhouse models, matching the temperatures inferred from high-lying molecular absorption lines in these galaxies.
  • A central dip or ring-like morphology of the HCN vibrational line is expected, since the optically thick line absorbs the bright millimeter continuum near the center.
  • For the diagnostics considered, AGN and starburst models give nearly identical HCN vibrational line fluxes, so the lines alone cannot distinguish the heating source; millimeter continuum peaks and central mass estimates are needed.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • Editorial inference: If real buried nuclei are clumpy or disk-like, the greenhouse heating is likely weaker than the spherical models predict, so the inferred surface brightness values should be read as upper bounds; reproducing the observed lines in a clumpy medium would require even higher columns or luminosities.
  • Editorial inference: The same trapped-radiation mechanism should boost vibrational lines of other cyanopolynes, such as HC$_3$N $\nu_7$ and $\nu_6$ and HNC, which the authors list as future work; the ratio of HC$_3$N to HCN vibrational lines could serve as a cleaner thermometer of the inner cocoon.
  • Editorial inference: Because the photon-diffusion timescale ($\sim 10^4$ yr) is comparable to AGN flickering timescales, a faded AGN could leave a fossil greenhouse cocoon that still emits HCN vibrational lines and shines at millimeter wavelengths, making a buried AGN resemble a starburst.
  • Editorial inference: The predicted steep rise of HCN vibrational luminosity with $\Sigma_{\rm IR}$ and its saturation at high columns can be tested by stacking unresolved galaxies that have measured compact dust masses; sources below a threshold of roughly $10^7\ L_\odot$ pc$^{-2}$ should show much weaker lines.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 4 minor

Summary. This paper presents spherically symmetric radiative-transfer models of buried galactic nuclei (BGNs) with high H2 columns and high luminosity surface densities, for both AGN-like central heating and distributed starburst heating. The authors compute dust temperature profiles and emergent SEDs, and post-process them with an HCN excitation model including the nu2=1 bending state. They find that for NH2 about 10^25 cm^-2 or more, trapping of infrared radiation enhances inner dust temperatures and the mean mid-infrared intensity by more than an order of magnitude, pumping HCN vibrational states so that the nu2=1 J=3-2 and 4-3 lines become optically thick. They use the model grid to interpret observed HCN vibrational fluxes in NGC 4418, Arp 220W/E, Zw 049.057, IC 860, and Mrk 231, inferring Sigma_IR around (0.5-2)e8 Lsun pc^-2 with X_HCN about 1e-6 and luminosities consistent with independent estimates. The paper also makes predictions for line ratios, spatial profile shapes, and millimeter continuum brightness.

Significance. If correct, the paper provides a quantitative physical basis for the bright HCN vibrational emission in buried nuclei: the greenhouse effect of infrared trapping makes the nu2=1 lines a natural luminosity-surface-density diagnostic. The modeling is carefully done and the paper gives credit where due: the continuum code conserves energy to better than 1%, is benchmarked against DUSTY (Appendix A.3), and the temperature profiles are provided as analytic fits (Tables 3-4). The paper also gives falsifiable predictions, including saturated line ratios near 1.8, a central brightness drop or ring morphology as observed in IC 860, and absorption of millimeter continuum by the lines. The main risk is that the core quantitative result is derived for smooth, isotropic, spherical density distributions, an assumption the authors acknowledge may overestimate dust temperatures in real clumpy or disk systems; this affects the derived Sigma_IR calibration. Nonetheless, the paper is a significant advance in modeling BGNs and provides a framework that can be tested against higher-resolution observations.

major comments (3)
  1. [Section 4 (Discussion) and Section 3.2.2 / Figure 2d] The authors state in Section 4 that the spherical symmetry 'assumes isotropic column densities from the center and no clumpiness' and that this 'oversimplified smoothed density structure may overestimate the dust temperature as compared with real systems.' This caveat bears directly on the central claim: the factor of at least 10 enhancement of the 14 micron mean intensity at NH2=10^25 cm^-2 (Figure 2d) and the resulting optically thick HCN nu2=1 lines are computed for a smooth, isotropic cocoon. In a clumpy or disk-like medium, radiation escapes along low-column sightlines, reducing the mean mid-infrared intensity that pumps nu2=1. Because the calibration in Figure 12 and Table 2 maps observed F_HCN/Delta_Omega to Sigma_IR through exactly this mechanism (equation 5), the inferred Sigma_IR and luminosities are upper limits unless a filling-factor or three-dimensional geometry test is performed. I request a quantitative sensitivity study, for example clumpy or disk models with conservative filling factors, or at minimum an explicit statement that all derived Sigma_IR are upper limits under the smooth-sphere assumption.
  2. [Section 3.1, Section 3.2.5, Figure 12, Table 2] The source comparison uses fiducial values X_HCN=10^-6 and Delta_V=67 km/s that are themselves partly motivated by previous analyses of the same sources (for example NGC 4418 and Arp 220), and the observed HCN fluxes are then used to infer Sigma_IR. The agreement in Figure 12 is therefore a demonstration of consistency rather than an independent inversion. The degeneracy is substantial: with the saturated-area scaling of equation (5), a factor of about 2 uncertainty in X_HCN, which the authors assign in Section 4, translates into a factor of more than 2 change in the inferred Sigma_IR for the same line flux. The paper should provide a joint constraint plot, such as the allowed Sigma_IR-X_HCN locus per source, or otherwise quantify how the inferred physical parameters depend on the assumed abundance and velocity dispersion.
  3. [Section 3.2.3 / Figure 11b] The comparison with Arp 220W's 2.6 mm brightness relies on an extrapolation: for NH2 above 10^25 cm^-2 the authors 'simply assumed that the Tdust profile remains the same as for NH2=10^25 cm^-2' and argue that the inferred brightness temperatures are lower limits because Tdust increases with NH2. This monotonic increase is plausible but is not demonstrated at these columns, and the increasing optical depth at 2.6 mm could instead saturate the brightness. A self-consistent radiative-transfer calculation for NH2 around 10^26 cm^-2, or an explicit argument for why the profile is unchanged, is needed to support the favorability claim for an AGN in Arp 220W based on the high 2.6 mm brightness.
minor comments (4)
  1. [Section 2.1] The phrase 'spectral enery distribution' is a typo and should read 'spectral energy distribution'.
  2. [Appendix A.1 and Figure 15 caption] The text contains 'an squematic approach' and the Figure 15 caption contains 'opticallt thin'; these should be corrected to 'a schematic approach' and 'optically thin'.
  3. [References] The reference 'Dekel, & Burkert 2014' is incomplete, lacking a journal or preprint identifier, and the in-text citation 'Förster Schreiber et al. 2003' appears in the reference list with the year 1993; these should be reconciled.
  4. [Section 3.2.2] Equation (5) is introduced with the remark that it is 'only valid for NHCN = 10^19 cm^-2'; the text should clarify whether this restriction also limits the applicability of the proportionality argument used in Section 3.2.4 for scaling line fluxes to other sources.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the greenhouse Tdust enhancement follows from radiative transfer, and the HCN line comparison is a calibration with independently motivated inputs.

full rationale

The paper's central claim—that high H2 columns trap continuum radiation and raise inner dust temperatures—is obtained by solving radiative transfer in spherical shells (Appendix A), with the code benchmarked against the independent DUSTY code (Fig. 16). The greenhouse effect and the factor >10 enhancement of mid-IR intensity are outputs of that calculation, not inputs taken from the HCN observations. The HCN vibrational line model then uses the computed Tdust profile together with X_HCN approximately 1e-6 and Delta V = 67 km/s, values adopted from prior far-IR absorption and 14 micron band analyses (Gonzalez-Alfonso et al. 2012; Lahuis et al. 2007), and predicts line fluxes, optical depths, and spatial profiles. The observed line fluxes are used in Fig. 12 to infer Sigma_IR and hence source luminosities, which the authors explicitly describe as a calibration; comparing those inferred luminosities with independent estimates is a consistency check rather than a circular derivation. Self-citations to the authors' earlier radiative-transfer and abundance work are not load-bearing in a circular sense because the method is described in the appendix and benchmarked, and the abundance inputs are independent of the greenhouse-effect result. The acknowledged spherical-symmetry and smooth-density limitation (Section 4) weakens applicability to clumpy or disk-like geometries but does not make the derivation circular. No step reduces by construction to its own inputs.

Assumptions & free parameters 9 free parameters · 7 assumptions · 0 invented entities

The central claims rest on a set of chosen model parameters and idealized physical assumptions, rather than on a self-contained derivation from first principles. The greenhouse effect magnitude depends on the smooth-sphere geometry and the adopted dust opacities, and the HCN line predictions require choosing the HCN abundance and velocity dispersion. None of these are invented entities, but several are free inputs calibrated to the very class of galaxies being explained.

free parameters (9)
  • Sigma_IR = (0.55-1.1)e8 Lsun/pc^2 fiducial; 0.14-2.2e8 explored; per-source inferred in Table 2
    Sets the radiation field that heats dust; free input, later inferred for each galaxy from HCN line brightness.
  • NH2 = 1e25 cm^-2 fiducial; 1e23-1e25 explored
    Sets dust optical depth and trapping strength; motivated by observed BGN columns but treated as a free parameter.
  • q = 1.0 fiducial, 1.5 explored
    Density power-law index n ~ r^-q; changes the Tdust profile and HCN excitation.
  • Rout/Rint = 17
    Outer-to-inner radius ratio fixed by hand; controls the cavity size.
  • X_HCN/Delta V = 1.5e-8 (km/s)^-1
    HCN abundance per unit velocity interval; chosen from prior abundance estimates and needed to match observed line fluxes.
  • Delta V = 67 km/s
    One-dimensional velocity dispersion; assumed uniform and source-independent.
  • Delta Omega = 1.1e-2 arcsec^2 fiducial; 0.008-0.15 arcsec^2 for sources
    Solid angle of the cocoon; sets absolute scale and is estimated from observed source sizes.
  • Dust opacity curve choice = red curve fiducial (beta=1.6), black curve alternative (beta=1.85)
    Mass absorption coefficient profile; Tdust profiles are nearly independent, but millimeter continuum and line absorption change.
  • Heating source type = AGN or SB
    Categorical choice determining luminosity distribution; both limits are modeled and compared.
assumptions (7)
  • domain assumption Spherical symmetry with a smooth, non-clumpy density distribution
    Load-bearing for the greenhouse effect; in clumpy or disk geometry radiation escapes and Tdust enhancement weakens. Stated in Section 2.1 and caveated in Section 4.
  • domain assumption Thermal equilibrium between gas and dust, Tgas = Tdust
    Used for HCN excitation models in Section 3.1; may fail in low-density outer regions if gas cooling and heating are imbalanced.
  • domain assumption Dust locally absorbs heating radiation and re-emits in the infrared; scattering is neglected
    Justified by high columns in Section 2.1; good approximation for BGNs.
  • domain assumption No velocity gradients in the HCN line radiative transfer
    Microturbulent broadening only; ignores large-scale motions that could alter line profiles and opacities, noted in Section 3.1.
  • domain assumption Gas-to-dust mass ratio of 100 and adopted dust absorption curves
    Converts NH2 to dust optical depth; the red and black curves are intended to bracket the true opacity, as described in Section 2.1 and Figure 1.
  • domain assumption Uniform HCN abundance across the source
    Simplifies excitation calculations; chemical models suggest strong temperature dependence, acknowledged in Section 4.
  • domain assumption AGN central heating source is a 1300 K blackbody
    Adopted in Section 2.1 to set the central source radius for a given AGN luminosity.

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Cite this review

Pith. "Pith review of The Greenhouse Effect in Buried Galactic Nuclei and the Resonant HCN Vibrational Emission." pith.science (2026). https://pith.science/paper/S3M6BCWM

@misc{pith2026190804058,
  author       = {Pith},
  title        = {Pith review of: The Greenhouse Effect in Buried Galactic Nuclei and the Resonant HCN Vibrational Emission},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/S3M6BCWM}},
  note         = {Machine review of arXiv:1908.04058}
}
abstract

Recent interferometric observations have shown bright HCN emission from the nu2=1 vibrational state arising in buried nuclear regions of galaxies, indicating an efficient pumping of the nu2=1 state through absorption of 14 $\mu$m continuum photons. We have modeled the continuum and HCN vibrational line emission in these regions, characterized by high column densities of dust and high luminosities, with a spherically symmetric approach, simulating both a central heating source (AGN) and a compact nuclear starburst (SB). We find that when the H2 columns become very high, N_{H2}>~10^{25} cm-2, trapping of continuum photons within the nuclear region dramatically enhances the dust temperature (Tdust) in the inner regions, even though the predicted spectral energy distribution as seen from outside becomes relatively cold. The models thus predict bright continuum at millimeter wavelengths for luminosity surface brightness (averaged over the model source) of ~10^{8} Lsun pc^{-2}. This {\it greenhouse} effect significantly enhances the mean mid-infrared intensity within the dusty volume, populating the nu2=1 state to the extent that the HCN vibrational lines become optically thick. AGN models yield higher Tdust in the inner regions and higher peak (sub)millimeter continuum brightness than SB models, but similar HCN vibrational J=3-2 and 4-3 emission owing to both optical depth effects and a moderate impact of high \tdust\ on these low-J lines. The observed HCN vibrational emission in several galaxies can be accounted for with a HCN abundance of ~10^{-6} (relative to H2) and luminosity surface brightness in the range (0.5-2)x10^{8}$ Lsun pc^{-2}, predicting a far-infrared photosphere with Tdust}~80-150 K --in agreement with the values inferred from far-infrared molecular absorption.

Figures

Figures reproduced from arXiv: 1908.04058 by the authors.

Figure 1
Figure 1. The two curves of mass absorption coefficient of dust as a function of wavelength considered in this work. We use as fiducial the red curve, with an emissivity index of β = 1.6 and κabs = 1.2 cm2 g −1 of dust at λ = 1.1 mm. highly idealized in sources with high column densities, where star formation is unavoidable, and represent an extreme limit still useful to potentially address, from comparison with SB models, th… view at source ↗
Figure 2
Figure 2. Results of two continuum models for an AGN-dominated source (solid lines) and two models for a starburst-dominated source (dashed lines), illustrating the greenhouse effect. The four models, shown with blue and red lines in panels a-c, have the same luminosity surface density (ΣIR = 5.5 × 107 L pc−2 ), solid angle (∆Ω = 1.1 × 10−2 arc sec2 ), and the density varies as r −1 (q = 1). The models differ only in the colu… view at source ↗
Figure 3
Figure 3. The black line indicates the thickness of the photosphere (∆r/Rout from the surface for τλ = 1, along the sightline that passes through the center of the source) as a function of wavelength (lower horizontal axis) for NH2 = 1025 cm−2 and q = 1. The colored lines show the calculated Tdust profile (upper horizontal axis) as a function of ∆r/Rout for the two models with NH2 = 1025 cm−2 of [PITH_FULL_IMAGE:figures/full… view at source ↗
Figures from the paper (17 more)
Figure 4
Figure 4. Figure 4: a) The ratio of ΥIR ≡ 4πr 2σSBTdust(r) 4 to the luminos￾ity of the source for the same models as in [PITH_FULL_IMAGE:figures/full_fig_p007_4.png]
Figure 5
Figure 5. Figure 5: Dependence of the mass-averaged Tdust on the surface brightness (ΣIR = LIR/πR 2 out), density profile (q), and fractional volume over which the average is performed. Full circles (solid lines) and open circles (dashed lines) indicate AGN and SB models, respectively. As…
Figure 6
Figure 6. Figure 6: Upper: Radial profiles of the acceleration (force per unit gas mass) due to radiation pressure on dust, for (a) AGN and (b) SB models, with parameters specified. The dark and light blue curves show the outward and inward accelerations, respectively, and the net (outwar…
Figure 7
Figure 7. Figure 7: The density profile for NH2 = 1025 cm−2 , Rout = 17 pc, and q = 1.0 − 1.5. In spherical symmetry, densities scale as ∝ NH2 R −1 out, but we neglect the R −1 out dependence to account for more general ge￾ometries (see text) [PITH_FULL_IMAGE:figures/full_fig_p009_7.png]
Figure 8
Figure 8. Figure 8: a-f) Comparison between the Tdust profiles (colored curves) and the excitation temperature of the HCN Q(3) (a-b), ν = 0J = 3 − 2 (c-d), and ν2 = 1f J = 3 − 2 (e-f) lines (overplotted dashed black curves). In our models we assume Tgas = Tdust. As indicated in panel a, t…
Figure 9
Figure 9. Figure 9: The velocity-integrated line optical depth along a radial path of the direct l-type HCN ν2 = 1J = 5 line at 6.73 GHz, for AGN (circles) and SB (stars) models with ΣIR = 5.5×107 L pc−2 and q = 1. We have also checked the excitation and optical depth of the direct l−type…
Figure 10
Figure 10. Figure 10: Detailed results for the same models as in Fig. 8a-c-e. a) The Tdust profiles. (b-c) The line profiles and (d-e) optical depths at line center of the HCN ν2 = 1f J = 3 − 2 and 4 − 3 transitions, with fiducial parameters (NHCN/∆V = 1.5×1017 cm−2 /(km s−1 ) and ∆V = 67 …
Figure 11
Figure 11. Figure 11: a) The brightness TB of the continuum at 1.1 mm (solid colored curves) and 2.6 mm (dashed) as a function of the impact parameter, for the fiducial models (AGN in red and SB in blue) with ΣIR = 1.1×108 L pc−2 . For comparison, the green curve indicates the NH2(p) profi…
Figure 12
Figure 12. Figure 12: a) The flux of the HCN ν2 = 1f J = 3 − 2 line per unit of solid angle of the source, as a function of the H2 column density. The right￾hand axis gives the source-averaged velocity-integrated brightness of the line. Each hatched region corresponds to a value of the con…
Figure 13
Figure 13. Figure 13: The ratio of the HCN ν2 = 1f J = 3 − 2 luminosity to the infrared luminosity of the source, as a function of ΣIR. Each hatched region corresponds to a value of the H2 column density as indicated, and is delimited by AGN (higher values) and SB (lower values) models. Ot…
Figure 14
Figure 14. Figure 14: Sketch of the modeled source. The radiation field is simulated by means of parallel rays (in red), each one representing the intensity in an interval [p − ∆p/2, p + ∆p/2]. After crossing a shell, the intensity is updated according to eq. (A2). These rays are used to c…
Figure 15
Figure 15. Figure 15: Example of convergence of our models. The two panels show with coloured curves the computed Tdust after each iteration (labeled with the iteration number), for the same model parameters but different initial temperatures. In the left panel, the initial Tdust were clos…
Figure 16
Figure 16. Figure 16: Comparison between the results of two of our models (coloured curves) and those obtain with the V4 version of the code DUSTY (Ivezic & Elitzur ´ 1997, 1999) (dashed black lines). The models are both optically thick (panel a), and the heating source is punctual with a …
Figure 17
Figure 17. Figure 17: The Tdust profiles for AGN models with q = 1.0 (ρ ∼ r −q ). Each panel shows results for fixed LIR/πR 2 and different H2 column densities (as indicated in the upper-left panel). The calculations use the red κν-curve of [PITH_FULL_IMAGE:figures/full_fig_p025_17.png]
Figure 18
Figure 18. Figure 18: Same as [PITH_FULL_IMAGE:figures/full_fig_p026_18.png]
Figure 19
Figure 19. Figure 19: Same as [PITH_FULL_IMAGE:figures/full_fig_p026_19.png]
Figure 20
Figure 20. Figure 20: Same as [PITH_FULL_IMAGE:figures/full_fig_p029_20.png]

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Works this paper leans on

72 extracted references · 63 canonical work pages

  1. [1]

    602C `\.=

    thebibliography [1] 20pt to REFERENCES 6pt =0pt 10pt plus 3pt =0pt =0pt =1pt plus 1pt =0pt =0pt -12pt =13pt plus 1pt =20pt =13pt plus 1pt \@M =10000 =-1.0em =0pt =0pt 0pt =0pt =1.0em @enumiv\@empty 10000 10000 `\.\@m \@noitemerr \@latex@warning Empty `thebibliography' environment \@ifnextchar \@reference \@latexerr Missing key on reference command Each re...

    work page 2016

  2. [2]

    2012, A&A, 537, 44

    Aalto, S., Garc\' a-Burillo, S., Muller, S., et al. 2012, A&A, 537, 44

    work page 2012

  3. [3]

    2015a, A&A, 574, A85

    Aalto, S., Garc\' a-Burillo, S., Muller, S., et al. 2015a, A&A, 574, A85

    work page

  4. [4]

    2015b, A&A, 584, A42

    Aalto, S., Mart\' n, S., Costagliola, F., et al. 2015b, A&A, 584, A42

    work page

  5. [5]

    Aalto, S., et al. in prep. 2019

    work page 2019

  6. [6]

    2018, A&A, 617, A20

    Aladro, R., K\"onig, S., Aalto, S., et al. 2018, A&A, 617, A20

    work page 2018

  7. [7]

    H., & Thompson, T

    Andrews, B. H., & Thompson, T. A. 2011, ApJ, 727, 97

    work page 2011

  8. [8]

    2010, A&A, 509, A50

    Cesaroni, R., Hofner, P., Araya, E., & Kurtz, S. 2010, A&A, 509, A50

    work page 2010

Show all 72 references
  1. [9]

    2017, MNRAS, 466, L103

    Chang, Y.Y., Le Floc'h, E., Juneau, S., et al. 2017, MNRAS, 466, L103

    2017

  2. [10]

    2010, A&A, 515, A71

    Costagliola, F., & Aalto, S. 2010, A&A, 515, A71

    2010

  3. [11]

    2013, 556, A66

    Costagliola, F., Aalto, S., Sakamoto, K.; Mart\' n, S., Beswick, R., Muller, S., & Kl\"ockner, H.-R. 2013, 556, A66

    2013

  4. [12]

    Dekel, & Burkert 2014

    2014

  5. [13]

    D., van Dishoeck, E

    Doty, S. D., van Dishoeck, E. F., & Tan, J. C. 2006, A&A, 454, L5

    2006

  6. [14]

    Downes, D., & Solomon, P. M. 1998, ApJ, 507, 615

    1998

  7. [15]

    2003, Annu

    Draine, B.T. 2003, Annu. Rev. Astr. Astrophys., 41, 241

    2003

  8. [16]

    2010, MNRAS, 406, 2488

    Dumouchel, F., Faure, A., & Lique, F. 2010, MNRAS, 406, 2488

    2010

  9. [17]

    P., Fischer, J., Veilleux, S., Mel\'endez, M., Farrah, D., & Smith, H

    Falstad, N., Gonz\'alez-Alfonso, E., Aalto, S., van der Werf, P. P., Fischer, J., Veilleux, S., Mel\'endez, M., Farrah, D., & Smith, H. A. 2015, A&A, 580, A52

    2015

  10. [18]

    Falstad, N., Gonz\'alez-Alfonso, E., Aalto, S., & Fischer, J., 2017, A&A, 597, A105

    2017

  11. [19]

    G., et al

    Falstad, N., Aalto, S., Mangum, J. G., et al. 2018, A&A, 609, A75

    2018

  12. [20]

    2019, A&A, in press

    Falstad, N., Hallqvist, F., Aalto, S., et al. 2019, A&A, in press

    2019

  13. [21]

    & Quataert, E

    Faucher-Gigu\`ere, C.-A. & Quataert, E. 2012, MNRAS, 425, 605

    2012

  14. [22]

    & Merritt, D

    Ferrarese, F. & Merritt, D

  15. [23]

    M., Genzel, R., Lutz, D., & Sternberg, A

    F\"orster Schreiber, N. M., Genzel, R., Lutz, D., & Sternberg, A. 1993, ApJ, 599, 193

    1993

  16. [24]

    Gebhardt, K., Bender, R., Bower, G.,

  17. [25]

    2015, A&A, 580, A35

    Garc\' a-Burillo, S., Combes, F., Usero, A., et al. 2015, A&A, 580, A35

    2015

  18. [26]

    1997, A&A, 322, 938

    Gonz\'alez-Alfonso, E., & Cernicharo, J. 1997, A&A, 322, 938

    1997

  19. [27]

    1999, ApJ, 525, 845

    Gonz\'alez-Alfonso, E., & Cernicharo, J. 1999, ApJ, 525, 845

    1999

  20. [28]

    A., Fischer, J., & Cernicharo, J

    Gonz\'alez-Alfonso, E., Smith, H. A., Fischer, J., & Cernicharo, J. 2004, ApJ, 613, 247

    2004

  21. [29]

    2012, A&A, 541, A4

    Gonz\'alez-Alfonso, E., Fischer, J., Graci\'a-Carpio, J., et al. 2012, A&A, 541, A4

    2012

  22. [30]

    2013, A&A, 550, A25

    Gonz\'alez-Alfonso, E., Fischer, J., Bruderer, S., et al. 2013, A&A, 550, A25

    2013

  23. [31]

    2014, A&A, 567, A91

    Gonz\'alez-Alfonso, E., Fischer, Aalto, S., & Falstad, N. 2014, A&A, 567, A91

    2014

  24. [32]

    2014b, A&A, 561, A27

    Gonz\'alez-Alfonso, E., Fischer, J., Graci\'a-Carpio, J., et al. 2014b, A&A, 561, A27

  25. [33]

    2015, ApJ, 800, 69

    Gonz\'alez-Alfonso, E., Fischer, J., Sturm, E, et al. 2015, ApJ, 800, 69

    2015

  26. [34]

    Gonz\'alez-Alfonso, E., Fischer, J., Spoon, H. W. W., et al. 2017, , 836, 11

    2017

  27. [35]

    2010, ApJ, 721, 1570

    Harada, N., Herbst, E., & Wakelam, V. 2010, ApJ, 721, 1570

    2010

  28. [36]

    F., Hernquist, L., Cox, T

    Hopkins, P. F., Hernquist, L., Cox, T. J., & Kere\^s, D. 2008, ApJS, 175, 356

    2008

  29. [37]

    2019, ApJ, 870, 75

    Ichikawa, K., Ueda, J., Bae, H.-J., Kawamuro, T., Matsuoka, K., Toba, Y., & Shidatsu, M. 2019, ApJ, 870, 75

    2019

  30. [38]

    2016a, AJ, 152, 218

    Imanishi, M., Nakanishi, K., & Izumi, T. 2016a, AJ, 152, 218

  31. [39]

    2016b, ApJ, 825, 44

    Imanishi, M., Nakanishi, K., & Izumi, T. 2016b, ApJ, 825, 44

  32. [40]

    1997, MNRAS, 287, 799

    Ivezi\'c, \^Z., & Elitzur, M. 1997, MNRAS, 287, 799

    1997

  33. [41]

    1999, MNRAS, 303, 864

    Ivezi\'c, \^Z., & Elitzur, M. 1999, MNRAS, 303, 864

    1999

  34. [42]

    Lahuis, F., Spoon, H. W. W., Tielens, A. G. G. M., et al. 2007, ApJ, 659, 296

    2007

  35. [43]

    D., et al

    Lusso, E., Comastri, A., Simmons, B. D., et al. 2012, MNRAS, 425, 623

    2012

  36. [44]

    2016, A&A, 590, A25

    Mart\' n, S., Aalto, S., Sakamoto, K., et al. 2016, A&A, 590, A25

    2016

  37. [45]

    R., Colangeli, L., Palumbo, P., Rotundi, A., & Bussoletti, E

    Mennella, V., Brucato, J. R., Colangeli, L., Palumbo, P., Rotundi, A., & Bussoletti, E. 1998, ApJ, 496, 1058

    1998

  38. [46]

    Nomura, H., & Millar, T. J. 2004, A&A, 414, 409

    2004

  39. [47]

    Planck Collaboration, 2011, A&A, 536, A25

    2011

  40. [48]

    J., & Faucher-Gigu\`ere, C.-A

    Richings, A. J., & Faucher-Gigu\`ere, C.-A. 2017, MNRAS

    2017

  41. [49]

    2004, ASSL, 308, 187

    Risaliti, G., & Elvis, M. 2004, ASSL, 308, 187

    2004

  42. [50]

    L., Riedinger, J

    Pilbratt, G. L., Riedinger, J. R.,

  43. [51]

    Poglitsch, A., Waelkens, C., Geis,

  44. [52]

    M., G\"usten, R., & Bisschop, S

    Rolffs, R., Schilke, P., Wyrowski, F., Menten, K. M., G\"usten, R., & Bisschop, S. E. 2011a, A&A, 527, A68

  45. [53]

    M., Thorwirth, S., & Belloche, A

    Rolffs, R., Schilke, P., Wyrowski, F., Dullemond, C., Menten, K. M., Thorwirth, S., & Belloche, A. 2011b, A&A, 529, A76

  46. [54]

    2011c, A&A, 536, A33

    Rolffs, R., Schilke, P., Zhang, Q., & Zapata, L. 2011c, A&A, 536, A33

  47. [55]

    F., & Quataert, E

    Roth, N., Kasen, D., Hopkins, P. F., & Quataert, E. 2012, ApJ, 759, 36

    2012

  48. [56]

    Phillips, P

    Rowan-Robinson, M., 1982, in ``Submillimeter Astronomy'', eds. Phillips, P. & Beckman, J. Cambridge Univ. Press, pg. 47

    1982

  49. [57]

    C., et al

    Sakamoto, K., Wang, J., Wiedner, M. C., et al. 2008, ApJ, 684, 957

    2008

  50. [58]

    J., et al

    Sakamoto, K., Aalto, S., Wilner, D. J., et al. 2009, ApJ, 700, L104

    2009

  51. [59]

    S., Wiedner, M

    Sakamoto, K., Aalto, S., Evans, A. S., Wiedner, M. C., & Wilner, D. J. 2010, ApJ, 725, L228

    2010

  52. [60]

    C., & Wilner, D

    Sakamoto, K., Aalto, S., Costagliola, F., Mart\' n, S., Ohyama, Y., Wiedner, M. C., & Wilner, D. J. 2013, ApJ, 764, 42

    2013

  53. [61]

    2017, ApJ, 849, 14

    Sakamoto, K., Aalto, S., Barcos-Mu\ noz, L., et al. 2017, ApJ, 849, 14

    2017

  54. [62]

    J., Ghosh, T., Catinella, B., Lebron, M., Lerner, M

    Salter, C. J., Ghosh, T., Catinella, B., Lebron, M., Lerner, M. S., Minchin, R., & Momjian, E. 2008, AJ, 136, 389

    2008

  55. [63]

    Salpeter, E. E. 1955, ApJ, 121, 161

    1955

  56. [64]

    Schawinski, K., Koss, M., Berney, S., & Sartori, L. F. 2015, MNRAS, 451, 2517

    2015

  57. [65]

    S., & Bryant, P

    Scoville, N., Yun, M. S., & Bryant, P. M. 1997, ApJ, 484, 702

    1997

  58. [66]

    2003, Journal of Korean Astronomical Society, 36, 167

    Scoville, N. 2003, Journal of Korean Astronomical Society, 36, 167

    2003

  59. [67]

    2017, ApJ, 836, 66

    Scoville, N., Murchikova, L., Walter, F., et al. 2017, ApJ, 836, 66

    2017

  60. [68]

    T., Neugebauer, G., Matthews, K., et al

    Soifer, B. T., Neugebauer, G., Matthews, K., et al. 2000, AJ, 119, 509

    2000

  61. [69]

    unken, S., M\

    Thorwirth, S., Wyrowski, F., Schilke, P., Menten, K. M., Br\"unken, S., M\"uller, H. S. P., & Winnewisser, G. ApJ, 586, 338

  62. [70]

    E., Mart\' -Vidal, I., Aalto, S., Beswick, R., Costagliola, F., & Kl\"ockner, H.-R

    Varenius, E., Conway, J. E., Mart\' -Vidal, I., Aalto, S., Beswick, R., Costagliola, F., & Kl\"ockner, H.-R. 2014, A&A, 566, A15

    2014

  63. [71]

    J., De Pree, C

    Wilner, D. J., De Pree, C. G., Welch, W. J., & Goss, W. M. 2001, ApJ, 550, L81

    2001

  64. [72]

    D., Rangwala, N., Glenn, J., Maloney, P

    Wilson, C. D., Rangwala, N., Glenn, J., Maloney, P. R., Spinoglio, L., & Pereira-Santaella, M. 2014, ApJ, 789, L36

    2014

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