Details

Autor(en) / Beteiligte

• Ramos Almeida, C
• Alonso-Herrero, A
• Levenson, N. A
• Asensio Ramos, A
• Rodríguez Espinosa, J. M
• González-Martín, O
• Packham, C
• Martínez, M

Titel

Investigating the sensitivity of observed spectral energy distributions to clumpy torus properties in Seyfert galaxies

Ist Teil von

• Monthly notices of the Royal Astronomical Society, 2014-04, Vol.439 (4), p.3847-3859

Ort / Verlag

London: Oxford University Press

Erscheinungsjahr

2014

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We present nuclear spectral energy distributions (SEDs) from 1 to 18 μm of a small sample of nearby, nearly face-on and undisturbed Seyfert galaxies without prominent nuclear dust lanes. These nuclear SEDs probe the central ∼35 pc of the galaxies, on average, and include photometric and spectroscopic infrared (IR) data. We use these SEDs, the clumpy torus models of Nenkova et al. and a Bayesian approach to study the sensitivity of different IR wavelengths to the torus parameters. We find that high angular resolution 8-13 μm spectroscopy alone reliably constrains the number of clumps and their optical depth (N 0 and τ V ). On the other hand, we need a combination of mid- and near-IR subarcsecond resolution photometry to constrain torus width and inclination, as well as the radial distribution of the clouds (σ, i and q). For flat radial profiles (q = 0, 1), it is possible to constrain the extent of the mid-IR-emitting dust within the torus (Y) when N-band spectroscopy is available, in addition to near-IR photometry. Finally, by fitting different combinations of average and individual Seyfert 1 and Seyfert 2 data, we find that, in general, for undisturbed, nearly face-on Seyferts without prominent nuclear dust lanes, the minimum combination of data necessary to reliably constrain all the torus parameters is J+K+M-band photometry + N-band spectroscopy.