Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gamma Rays From Rotation-Powered Pulsars   The seven known gamma-ray pulsars represent a very small fraction of the more
than 1000 presently known radio pulsars, yet they can give us valuable
information about pulsar particle acceleration and energetics. Although the
theory of acceleration and high-energy emission in pulsars has been studied for
over 25 years, the origin of the pulsed gamma rays is a question that remains
unanswered. Characteristics of the pulsars detected by the Compton Gamma-Ray
Observatory could not clearly distinguish between an emission site at the
magnetic poles (polar cap models) and emission from the outer magnetosphere
(outer gap models). There are also a number of theoretical issues in both type
of model which have yet to be resolved. The two types of models make
contrasting predictions for the numbers of radio-loud and radio-quiet gamma-ray
pulsars and of their spectral characteristics. GLAST will probably detect at
least 50 radio-selected pulsars and possibly many more radio-quiet pulsars.
With this large sample, it will be possible to fully test the model predictions
and finally resolve this longstanding question.

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The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
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The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th