Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Probing the Cosmic Ray Population of the Giant Elliptical Galaxy M 87
  with Observed TeV Gamma-Rays   We examine the cosmic ray proton (CRp) population within the giant elliptical
galaxy M 87 using the TeV gamma-ray detection of the HEGRA collaboration. In
our scenario, the gamma-rays are produced by decaying pions which result from
hadronic CRp interactions with thermal gas of the interstellar medium of M 87.
By comparing the gamma-ray emission to upper limits of EGRET, we constrain the
spectral index of the CRp population to alpha(GeV,TeV) < 2.275 within our
scenario. Both the expected radial gamma-ray profile and the required amount of
CRp support this hadronic scenario. The accompanying radio mini-halo of
hadronically originating cosmic ray electrons is outshone by the synchrotron
emission of the relativistic jet of M 87 by one order of magnitude. According
to our predictions, the future GLAST mission should allow us to test this
hadronic scenario.

4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con