Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Radiation Transfer of Emission Lines in Curved Space-Time   We present a general formulation for ray-tracing calculations in curved
space-time. The formulation takes full account of relativistic effects in the
photon transport and the relative motions of the emitters and the
light-of-sight absorbing material. We apply the formulation to calculate the
emission from accretion disks and tori around rotating black holes.

22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
28
The categories of this paper are: alg-geom