3D Radiation hydrodynamics of a dynamical torus
  We have developed a new dynamical model of the torus region in active
galactic nucleus (AGN), using a three-dimensional radiation hydrodynamics
algorithm. These new simulations have the specific aim to explore the role of
radiatively-driven outflows, which is hotly debated in current literature as a
possible explanation for the observed infrared emission from the polar regions
of AGN. In this first paper, we only consider radiative effects induced by the
primary radiation from the AGN. The simulations generate a disk & outflow
structure that qualitatively agrees with observations, although the outflow is
radial rather than polar, likely due to the lack of radiation pressure from hot
dust. We find cut-offs between the wind and disk at gas temperatures of 1000 K
and dust temperatures of 100 K, producing kinematic signatures that can be used
for interpretation of high resolution infrared observations. We also produce
line emission maps to aid in the interpretation of recent ALMA observations and
future JWST observations. We investigate a number of simulation parameters, and
find that the anisotropy of the radiation field is equally important to the
Eddington factor, despite the anisotropy often being assumed to have a single
sometimes arbitrary form in many previous works. We also find that supernovae
can have a small but significant impact, but only at extremely high star
formation rates.
