Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gamma-Ray Pulsars   Gamma-ray photons from young pulsars allow the deepest insight into the
properties and interactions of high-energy particles with magnetic and photon
fields in a pulsar magnetosphere. Measurements with the Compton Gamma-Ray
Observatory have led to the detection of nearly ten gamma-ray pulsars. Although
quite a variety of individual signatures is found for these pulsars, some
general characteristics can be summarized: (1) the gamma-ray lightcurves of
most high-energy pulsars show two major peaks with the pulsed emission covering
more than 50% of the rotation, i.e. a wide beam of emission; (2) the gamma-ray
spectra of pulsars are hard (power law index less than 2), often with a
luminosity maximum around 1 GeV. A spectral cutoff above several GeV is found;
(3) the spectra vary with rotational phase indicating different sites of
emission; and (4) the gamma-luminosity scales with the particle flux from the
open regions of the magnetosphere (Goldreich-Julian current).

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The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
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The categories of this paper are: eess
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The categories of this paper are: cmp-lg
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn