Radiation Pressure Supported AGN Tori with Hard X-Ray and Stellar Heating

Abstract

The dynamics and structure of toroidal obscuration around AGN remain uncertain and controversial. In this paper we extend earlier work on the dynamical role of infrared radiation pressure by adding the effects of two kinds of distributed heating: Compton-heating due to hard X-rays from the nucleus and local starlight heating. We find numerical solutions to the axisymmetric hydrostatic equilibrium, energy balance, and photon diffusion equations including these effects. Within the regime of typical parameters, the two different sources of additional heating have very similar effects: the density profile within the torus becomes shallower both radially and vertically, but for plausible heating rates, there is only minor change (relative to the source-free case) in the distribution of column density with solid angle. The most interesting consequence of distributed heating is that it selects out a relatively narrow range of parameters permitting an equilibrium, particularly $(L/L_E)/{\tau }_T$. We discuss the implications of both the narrowness of the permitted range and its approximate coincidence with the range inferred from observations.

27 pages, 8 figures, accepted by ApJ

References in corpus (5)

• A Close Look at Star Formation around Active Galactic Nuclei
• X-ray spectral properties of AGN in the Chandra Deep Field South
• Suzaku Observations of Active Galactic Nuclei Detected in the Swift/BAT Survey: Discovery of "New Type" of Buried Supermassive Black Holes
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Cited by in corpus (5)

• Feedback from central black holes in elliptical galaxies. I: models with either radiative or mechanical feedback but not both
• Obscuring Active Galactic Nuclei with Nuclear Starburst Disks
• Geometrically thick obscuration by radiation-driven outflow from magnetized tori of active galactic nuclei
• Radiation hydrodynamics models of Active Galactic Nuclei: Beyond the central parsec
• Parsec-scale obscuring accretion disk with large scale magnetic field in AGN