Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The role of advection in the accreting corona model for active galactic
  nuclei and Galactic black holes   We consider the role of advection in the two-temperature accreting corona
with an underlying optically thick disc. The properties of coronal solutions
depend significantly on the description of advection. Local parameterization of
advection by a constant coeficient $\delta$ replacing the radial derivatives
lead to complex topology of solutions, similar to some extent to other
advection-dominated accretion flow solutions. One, radiatively cooled branch
exists for low accertion rates. For higher accretion rates two solutions exist
in a broad range of radii: one is radiatively cooled and the other one is
advection-dominated. With further increase of accretion rate the radial
extensions of the two solutions shrink and no solutions are found above certain
critical value. However, these trends change if the local parameterization of
advection is replaced by proper radial derivatives computed iteratively from
the model. Only one, radiatively cooled solution remains, and it exists even
for high accretion rates. The advection-dominated branch disappears during the
iteration process which means that a self-consistently described
advection-dominated flow cannot exist in the presence of an underlying cold
disc.

10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
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The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
23
The categories of this paper are: solv-int