Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Galaxy population properties in the rich clusters MS0839.8+2938,
  1224.7+2007 and 1231.3+1542   This paper discusses the galaxy populations of three rich clusters, with
redshift 0.19 (0839+29), 0.24 (1231+15), and 0.32 (1224+20), from the database
of the CNOC1 consortium. The data consist of spectra of 52 cluster members for
0839+29, 30 members for 1224+15, and 82 members for 1231+15, and there are
comparable numbers of field galaxy spectra. 0839+29 is compact with no strong
radial gradients, and possibly dusty. 1224+20 is isolated in redshift, has low
velocity dispersion around the cD galaxy, and low 4000A break. 1231+15 is
asymmetrical and we discuss the possibility that it may be a recent merger of
two old clusters. We find few galaxies in 0839+29 and 1231+15 with ongoing or
recently truncated star-formation.

15
The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
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The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-lat
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The categories of this paper are: alg-geom
2
The categories of this paper are: math
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The categories of this paper are: comp-gas
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The categories of this paper are: adap-org
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The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
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The categories of this paper are: eess
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The categories of this paper are: q-bio