Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relativistic two-photon bremsstrahlung   An approximate approach for the description of the two-photon bremsstrahlung
emitted by a relativistic projectile scattered in a spherically-symmetric field
is developed. It based on the accurate treatment of the analytical structure of
the singularities in relativistic one-photon free-free matrix elements. For the
case of a Coulomb field the analytical expressions for the amplitude and cross
section of process are presented. Numerical results obtained within the
framework of the proposed approach are compared with the available experimental
data and with the results of simpler theories.

12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
16
The categories of this paper are: stat