Parsec-scale obscuring accretion disk with large scale magnetic field in AGN

Abstract

Magnetic field dragged from the galactic disk along with inflowing gas can provide vertical support to the geometrically and optically thick pc-scale torus in AGN. Using the Soloviev solution initially developed for Tokamaks we derive an analytical model for a rotating torus supported and confined by magnetic field. We further perform three-dimensional magneto-hydrodynamics simulations of X-ray irradiated pc-scale magnetized tori. We follow the time evolution and compare models which adopt initial conditions derived from our analytic model with simulations in which the initial magnetic flux is entirely contained within the gas torus. Numerical simulations demonstrate that the initial conditions based on the analytic solution produce a longer-lived torus and one which produces obscuration which is generally consistent with observed constraints.