Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spherical Accretion with Anisotropic Thermal Conduction   We study the effects of anisotropic thermal conduction on magnetized
spherical accretion flows using global axisymmetric MHD simulations. In low
collisionality plasmas, the Bondi spherical accretion solution is unstable to
the magnetothermal instability (MTI). The MTI grows rapidly at large radii
where the inflow is subsonic. For a weak initial field, the MTI saturates by
creating a primarily radial magnetic field, i.e., by aligning the field lines
with the background temperature gradient. The saturation is quasilinear in the
sense that the magnetic field is amplified by a factor of $\sim 10-30$
independent of the initial field strength (for weak fields). In the saturated
state, the conductive heat flux is much larger than the convective heat flux,
and is comparable to the field-free (Spitzer) value (since the field lines are
largely radial). The MTI by itself does not appreciably change the accretion
rate $\dot M$ relative to the Bondi rate $\dot M_B$. However, the radial field
lines created by the MTI are amplified by flux freezing as the plasma flows in
to small radii. Oppositely directed field lines are brought together by the
converging inflow, leading to significant resistive heating. When the magnetic
energy density is comparable to the gravitational potential energy density, the
plasma is heated to roughly the virial temperature; the mean inflow is highly
subsonic; most of the energy released by accretion is transported to large
radii by thermal conduction; and the accretion rate $\dot M \ll \dot M_B$. The
predominantly radial magnetic field created by the MTI at large radii in
spherical accretion flows may account for the stable Faraday rotation measure
towards Sgr A* in the Galactic Center.

16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
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The categories of this paper are: adap-org
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The categories of this paper are: q-fin
2
The categories of this paper are: math
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The categories of this paper are: solv-int
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The categories of this paper are: funct-an
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The categories of this paper are: cond-mat
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The categories of this paper are: nlin