Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Morphologies in a Cluster of Extremely Red Galaxies with Old Stellar
  Populations at z=1.34   We have identified a clustering of red galaxies from deep optical/IR images
obtained as part of the Institute for Astronomy Deep Survey. Photometric
spectral-energy distributions indicate that most of these galaxies comprise
nearly pure old stellar populations at a redshift near 1.4, and Keck
spectroscopy of the three brightest red galaxies confirm this interpretation
and give redshifts ranging from 1.335 to 1.338. Four of the galaxies are close
together on the sky and less than 30" from an R=13.5 star, and we have obtained
deep adaptive-optics imaging of this group. Detailed analysis and modeling of
the surface-brightness profiles of these galaxies shows that two are normal
ellipticals, one is an S0, and one appears to be an essentially pure disk of
old stars, with no significant bulge. All four are highly relaxed, symmetric
systems. While the old, bulgeless disk galaxy represents a type that is rare at
the present epoch, the other three galaxies have structural parameters that are
essentially indistinguishable from those of present-day galaxies and differ
only in the age of their stellar populations.

26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin
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The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
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The categories of this paper are: comp-gas
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The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex