Fermi Gamma-ray Space Telescope

MHD Winds, AGN Unification Torii and the Blazar Sequence

D. Kazanas
K. Fukumura, M. Georganopoulos, C. R. Shrader, S. T. Scully

Abstract:

We model blazar emission with emphasis on its broad characteristics, i.e. Synchrotron or Compton dominance, within the broader framework of MHD accretion disk winds. We show that these winds, which can serve as the Molecular Torii invoked to account for AGN Unified Models and also reproduce the AGN Warm Absorber properties, have significant impact on the SED distribution of blazars. This is due to their density profiles, which have been shown to have a very strong polar angle dependence and radial dependence close to 1/r. This latter property, because it allows scattering of the central source continuum with equal probability at all radii, is instrumental in the determination of the ambient photon density (and hence the Compton dominance) of a source at distances as large as 10 pc from the BH. We show that for sources radiating at less than ~0.01 of their Eddington limit, the magnetic field dominates the local photon density and the sources transit from the FSRQ to the BL Lac class in agreement with the blazar sequence.