Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Isotropic diffuse and extragalactic $\gamma$-ray background: emission
  from extragalactic sources vs dark matter annihilating particles   The isotropic diffuse $\gamma$-ray background (IGRB) has been detected by
various experiments and recently the Fermi-LAT Collaboration has precisely
measured its spectrum in a wide energy range. The origin of the IGRB is still
unclear and we show in this paper the significative improvements that have been
done, thanks to the new Fermi-LAT catalogs, to solve this mystery. We
demonstrate that the $\gamma$-ray intensity and spectrum of the IGRB is fully
consistent with the unresolved emission from extragalactic point sources,
namely Active Galactic Nuclei and Star Forming Galaxies. We show also that the
IGRB can be employed to derive sever constraints for the $\gamma$-ray emission
from diffuse processes such as annihilation of Dark Matter (DM) particles. Our
method is able to provide low bounds for the thermal annihilation cross section
for a wide range of DM masses.

27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
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
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio