THREE-DIMENSIONAL RADIATIVE TRANSFER CALCULATIONS OF RADIATION FEEDBACK FROM MASSIVE BLACK HOLES: OUTFLOW OF MASS FROM THE DUSTY 'TORUS'
Observational and theoretical arguments suggest that the momentum carried in mass outows from AGN can reach several times L=c, corresponding to outow rates of hundreds of solar masses per year. Radiation pressure on resonant absorption lines alone may not be sucient to provide this momentum deposition, and the transfer of reprocessed IR radiation in dusty nuclear gas has been postulated to provide the extra enhancement. The ecacy of this mechanism, however, will be sensitive to multidimensional eects such as the tendency for the reprocessed radiation to preferentially escape along sightlines of lower column density. We use Monte Carlo radiative transfer calculations to determine the radiation force on dusty gas residing within approximately 30 parsecs from an accreting supermassive black hole. We calculate the net rate of momentum deposition in the surrounding gas and estimate the mass-loss rate in the resulting outow as a function of solid angle for dierent black hole luminosities, sightline-averaged column densities, clumping parameters, and opening angles of the dusty gas. We nd that these dust-driven winds carry momentum uxes of 1-5 times L=c and correspond to mass-loss rates of 10-100 M per year for a 10 8 M black hole radiating at or near its Eddington limit. These results help to explain the origin of high velocity molecular and atomic outows in local ULIRGs, and can inform numerical simulations of galaxy evolution including AGN feedback. Subject headings: black hole physics { galaxies: active { galaxies: kinematics and dynamics { galaxies: nuclei { radiative transfer { quasars: general