Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: FIRST-radio sources in clusters of galaxies   The detailed identifications of the FIRST and NVSS radio sources with optical
objects in APM and in DSS surveys are carried out for 26 rich Abell clusters of
galaxies. 99 radio sources are identified with optical objects, 40 have
probable identifications, and 187 are not identified from 326 radio sources in
the considered fields (within Abell radius of each cluster of galaxies). 20
radio sources are definitely in clusters and 34 can be clusters members with
high confidence. Therefore, ~30-40% of the FIRST radio sources can be
identified with optical objects on the base of APM and of DSS data. On average,
one can find 2 identified sources per cluster.

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The categories of this paper are: chao-dyn
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The categories of this paper are: bayes-an
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The categories of this paper are: ao-sci
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The categories of this paper are: stat
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The categories of this paper are: math
1
The categories of this paper are: cs
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The categories of this paper are: patt-sol
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The categories of this paper are: q-alg
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The categories of this paper are: quant-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: nlin
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The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ph
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The categories of this paper are: math-ph
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The categories of this paper are: atom-ph