Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cosmic Ray Studies with the Fermi Gamma-ray Space Telescope Large Area
  Telescope   The Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope
provides both direct and indirect measurements of Galactic cosmic rays (CR).
The LAT high-statistics observations of the 7 GeV - 1 TeV electron plus
positron spectrum and limits on spatial anisotropy constrain models for this
cosmic-ray component. On a Galactic scale, the LAT observations indicate that
cosmic- ray sources may be more plentiful in the outer Galaxy than expected or
that the scale height of the cosmic-ray diffusive halo is larger than
conventional models. Production of cosmic rays in supernova remnants (SNR) is
supported by the LAT gamma-ray studies of several of these, both young SNR and
those interacting with molecular clouds.

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The categories of this paper are: alg-geom
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The categories of this paper are: nlin
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
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The categories of this paper are: math-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int
3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: eess
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The categories of this paper are: q-fin
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The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol