Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Line-driven winds in presence of strong gravitational fields   We propose a general physical mechanism which could contribute to the
formation of fast line-driven outflows at the vicinity of strong gravitational
field sources. We argue that the gradient of the gravitational potential plays
the same role as the velocity gradient plays in Sobolev approximation. Both
Doppler effect and gravitational redshifting are taken into account in Sobolev
approximation. The radiation force becomes a function of the local velocity
gradient and the gradient of the gravitational potential. The derived equation
of motion has a critical point that is different from that of CAK. A solution
that is continuous through the singular point is obtained numerically. A
comparison with CAK theory is presented. It is shown that the developed theory
predicts terminal velocities which are greater than those obtained from the CAK
theory.

4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
2
The categories of this paper are: math
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
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The categories of this paper are: physics
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol