Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Imaging of Three Possible Low Redshift Analogs to High Redshift Compact
  Red Galaxies   As part of a larger program to identify and characterize possible
low-redshift analogs to massive compact red galaxies found at high redshift, we
have examined the morphologies of three low-redshift compact galaxies drawn
from the sample of Trujillo et al. (2009). Using deeper and higher resolution
images, we have found faint and relatively extensive outer structures in
addition to the compact cores identified in the earlier measurements. One
object appears to have a small companion that may be involved in an ongoing
minor merger of the sort that could be responsible for building up the outer
parts of these galaxies. The ages of the dominant stellar populations in these
objects are found to be around 2--4 Gyr, in good agreement with the previous
estimates. The presence of diffuse outer structures in these galaxies indicates
that truly compact and massive red galaxies are exceedingly rare at low
redshift. The relatively young stellar populations suggest that the accretion
of the extensive outer material must occur essentially universally on
relatively short timescales of few billion years or less. These results confirm
and extend previous suggestions that the driving mechanism behind the size
evolution of high redshift compact galaxies cannot be highly stochastic
processes such as major mergers, which would inevitably leave a non-negligible
fraction of survivors at low redshift.

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The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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The categories of this paper are: supr-con
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The categories of this paper are: solv-int
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The categories of this paper are: funct-an
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The categories of this paper are: stat
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The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
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The categories of this paper are: math
32
The categories of this paper are: atom-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: nlin
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The categories of this paper are: dg-ga
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The categories of this paper are: ao-sci