Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Photon number emission in synchrotron radiation: Systematics for
  high-energy particles   A recent derivation of an explicit elementary expression for the mean number
$<N>$ of photons emitted per revolution in synchrotron radiation allows a
systematic high-energy analysis leading to the result $<N>\simeq
5\pi\alpha/\sqrt{3(1-\beta^2)}+a_0\alpha+\pi\alpha\sqrt{1-\beta^2}/10\sqrt{3}$
where $a_0$ is a constant, with relative errors of 2.2%, 0.64%, 0.017%, in
comparison to the well-known formula tabulated in the literature of 160%, 82%,
17% for $\beta=0.8$, 0.9, 0.99, respectively.

20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom