Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observations of the young supernova remnant RX J1713.7-3946 with the
  Fermi Large Area Telescope   We present observations of the young Supernova remnant (SNR) RX J1713.7-3946
with the Fermi Large Area Telescope (LAT). We clearly detect a source
positionally coincident with the SNR. The source is extended with a best-fit
extension of 0.55$^{\circ} \pm 0.04^{\circ}$ matching the size of the
non-thermal X-ray and TeV gamma-ray emission from the remnant. The positional
coincidence and the matching extended emission allows us to identify the LAT
source with the supernova remnant RX J1713.7-3946. The spectrum of the source
can be described by a very hard power-law with a photon index of $\Gamma = 1.5
\pm 0.1$ that coincides in normalization with the steeper H.E.S.S.-detected
gamma-ray spectrum at higher energies. The broadband gamma-ray emission is
consistent with a leptonic origin as the dominant mechanism for the gamma-ray
emission.

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The categories of this paper are: eess
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
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The categories of this paper are: adap-org
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
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The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph