The Galaxy Activity, Torus and Outflow Survey (GATOS): II. Torus and polar dust emission in nearby Seyfert galaxies

Abstract

We compare high angular resolution mid-infrared (mid-IR) and ALMA far-infrared (far-IR) images of twelve nearby (median 21 Mpc) Seyfert galaxies selected from the Galaxy Activity Torus and Outflow Survey (GATOS). The mid-IR unresolved emission contributes more than 60% of the nuclear (diameters of 1.5 ∼150 pc) emission in most galaxies. By contrast, the ALMA 870 µm continuum emission is mostly resolved with a median diameter of 42 pc and typically along the equatorial direction of the torus (Paper I of the series Garcia-Burillo et al. 2021). The Eddington ratios and nuclear hydrogen column densities (N H ) of half the sample are favorable to launching polar and/or equatorial dusty winds, according to numerical simulations. Six of these show mid-IR extended emission approximately in the polar direction as traced by the narrow line region and perpendicular to the ALMA emission. In a few galaxies, the nuclear N H might be too high to uplift large quantities of dusty material along the polar direction. Five galaxies have low N H and/or Eddington ratios and thus polar dusty winds are not likely. We generate new radiative transfer CAT3D-WIND disk-wind models and model images at 8, 12, and 700 µm. We tailor these models to the properties of the GATOS Seyferts in this work. At low wind-to-disk cloud ratios the far-IR model images have disk-and ring-like morphologies. The characteristic "X"-shape associated with dusty winds is seen better in the far-IR at intermediate-high inclinations for the extended-wind configurations. In most of the explored models, the mid-IR emission comes mainly from the inner part of the disk/cone. Extended bi-conical and one-sided polar mid-IR emission is seen in extended-wind configurations and high wind-to-disk cloud ratios. When convolved to the typical angular resolution of our observations, the CAT3D-WIND model images reproduce qualitative aspects of the observed mid-and far-IR morphologies. However, low to intermediate values of the wind-to-disk ratio are required to account for the observed large fractions of unresolved mid-IR emission in our sample. This work and Paper I provide observational support for the torus+wind scenario. The wind component is more relevant at high Eddington ratios and/or AGN luminosities, and polar dust emission is predicted at nuclear column densities of up to ∼ 10 24 cm −2 . The torus/disk component, on the other hand, prevails at low luminosities and/or Eddington ratios.

Warm Absorbers in the Radiation-driven Fountain Model of Low-mass Active Galactic Nuclei

“…Outflows in various physical conditions are ubiquitously observed from an active galactic nuclei (AGN). They constitute essential elements of the AGN structure, such as jets, warm absorbers, narrow emission line regions (NLRs), and tori (e.g., Elitzur & Shlosman 2006;Netzer 2015;Wada et al 2018b;Alonso-Herrero et al 2021). By carrying a huge amount of mass, momentum, and energy from the nucleus, these AGN-driven outflows play key roles in determining the dynamics of accretion flow onto the supermassive black hole (SMBH), and even significantly affect its environment in the host galaxy or larger scale (e.g., Fabian 2012;Harrison 2017;Veilleux et al 2020).…”

Complementary dataset of the paper "The viewing angle in AGN SED models, a data-driven analysis"

“…For example, Hönig & Kishimoto (2017) propose a model where dusty winds can explain the observational results on spatially resolved AGNs (e.g. García-Burillo et al 2021;Alonso-Herrero et al 2021). Later on, this model was extended by Hönig (2019), following interferometry IR and submm observations (e.g.…”