Viscous-Resistive ADAF with a general Large-Scale Magnetic Field
  We have studied the structure of hot accretion flow bathed in a general
large-scale magnetic field. We have considered magnetic parameters $
\beta_{r,\varphi,z}[=c^2_{r,\varphi,z}/(2c^2_{s})] $, where $ c^2_{r, \varphi,
z} $ are the Alfv\'{e}n sound speeds in three direction of cylindrical
coordinate $ (r,\varphi,z) $. The dominant mechanism of energy dissipation is
assumed to be the magnetic diffusivity due to turbulence and viscosity in the
accretion flow. Also, we adopt a more realistic model for kinematic viscosity $
(\nu=\alpha c_{s} H) $, with both $ c_{s} $ and $ H $ as a function of magnetic
field. As a result in our model, the kinematic viscosity and magnetic
diffusivity $ (\eta=\eta_{0}c_{s} H) $ are not constant. In order to solve the
integrated equations that govern the behavior of the accretion flow, a
self-similar method is used. It is found that the existence of magnetic
resistivity will increase the radial infall velocity as well as sound speed and
vertical thickness of the disk. However the rotational velocity of the disk
decreases by the increase of magnetic resistivity. Moreover, we study the
effect of three components of global magnetic field on the structure of the
disk. We found out that the radial velocity and sound speed are Sub-Keplerian
for all values of magnetic field parameters, but the rotational velocity can be
Super-Keplerian by the increase of toroidal magnetic field. Also, Our numerical
results show that all components of magnetic field can be important and have a
considerable effect on velocities and vertical thickness of the disk.
