Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Las Campanas/AAT Rich Cluster Survey III: Spectroscopic Studies of
  X-ray Bright Galaxy Clusters at z~0.1   [abridged] We present the analysis of the spectroscopic and photometric
catalogues of 11 X-ray luminous clusters at z=0.07-0.16 from the Las Campanas /
Anglo-Australian Telescope Rich Cluster Survey. Our spectroscopic dataset
consists of over 1600 galaxy cluster members, of which two thirds are outside
r_200. We assign cluster membership using a detailed mass model and expand on
our previous work on the cluster colour-magnitude relation where membership was
inferred statistically. We confirm that the modal colours of galaxies on the
colour magnitude relation become progressively bluer with increasing radius and
decreasing local galaxy density. Interpreted as an age effect, we hypothesize
that these trends in galaxy colour should be reflected in mean Hdelta
equivalent width. We confirm that passive galaxies in the cluster increase in
Hdelta line strength as dHdelta / d r_p = 0.35 +/- 0.06. A variation of star
formation rate, as measured by [OII], with increasing local density of the
environment is discernible and is shown to be in broad agreement with previous
studies from 2dFGRS and SDSS. We find that clusters at z~0.1 are less active
than their higher redshift analogues. We also investigate unusual populations
of blue and very red nonstarforming galaxies and we suggest that the former are
likely to be the progenitors of galaxies which will lie on the colour-magnitude
relation, while the colours of the latter possibly reflect dust reddening. The
cluster galaxies at large radii consist of both backsplash ones and those that
are infalling to the cluster for the first time. We make a comparison to the
field population at z~0.1 and examine broad differences between the two
populations. Individually, the clusters show significant variation in their
galaxy populations which reflects their recent infall histories.

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The categories of this paper are: stat
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The categories of this paper are: eess
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The categories of this paper are: acc-phys
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The categories of this paper are: q-bio
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The categories of this paper are: math-ph
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The categories of this paper are: hep-ph
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The categories of this paper are: q-fin
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The categories of this paper are: hep-th
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The categories of this paper are: econ
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The categories of this paper are: patt-sol
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The categories of this paper are: funct-an
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The categories of this paper are: math
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The categories of this paper are: plasm-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: quant-ph
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The categories of this paper are: supr-con