Kazem Faghei, Azam Mollatayefeh
The existence of outflow in accretion flows is confirmed by observations and
magnetohydrodynamics (MHD) simulations. In this paper, we study outflows of
accretion flows in the presence of resistivity and toroidal magnetic field. The
mechanism of energy dissipation in the flow is assumed to be the viscosity and
the magnetic diffusivity due to turbulence in the accretion flow. It is also
assumed that the magnetic diffusivity and the kinematic viscosity are not
constant and vary by position and $\alpha$-prescription is used for them. The
influence of outflow emanating from accretion disc is considered as a sink for
mass, angular momentum and energy. The self-similar method is used to solve the
integrated equations that govern the behavior of the accretion flow in the
presence of outflow. The solutions represent the disc which rotates faster and
becomes cooler for stronger outflows. Moreover, by adding the magnetic
diffusivity, the surface density and rotational velocity decrease, while the
radial velocity and temperature increase. The study of present model with the
magnitude of magnetic field implies that the disc rotates and accretes faster
and becomes hotter, while the surface density decreases. The disc thickness
increases by adding the magnetic field or resistivity, while it becomes thinner
for more losses of mass and energy due to the outflows.
View original:
http://arxiv.org/abs/1202.3095
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