Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Evolution of Early-Type Galaxies in Distant Clusters III.: M/L_V
  Ratios in the z=0.33 Cluster CL1358+62   Keck spectroscopy and Hubble Space Telescope WFPC2 imaging over a 1.5x1.5 Mpc
field of CL1358+62 at z=0.33 are used to study the Fundamental Plane of
galaxies based on a new, large sample of 53 galaxies. First, we have
constructed the Fundamental Plane for the 30 E and S0 galaxies and find that it
has the following shape: r_e = sigma**(1.31+-0.13) * <I>_e**(-0.86+-0.10),
similar to that found locally. The 1-sigma intrinsic scatter about this plane
is 14% in M/L(V), comparable to that observed in Coma. We conclude that these E
and S0 galaxies are structurally mature and homogeneous, like those observed in
nearby clusters. The M/L(V) ratios of these early-type galaxies are offset from
the Coma Fundamental Plane by delta log M/L(V) = -0.13+- 0.03 (q0=0.1),
indicative of mild luminosity evolution. This evolution suggests a formation
epoch for the stars of z > 1. We have also analyzed the M/L(V) ratios of
galaxies of type S0/a and later. These early-type spirals follow a different
plane from the E and S0 galaxies, with a scatter that is twice as large as the
scatter for the E/S0s. The difference in the tilt between the plane of the
spirals and the plane of the E/S0s is shown to be due to a systematic
correlation of velocity dispersion with residual from the plane of the
early-type galaxies. These residuals also correlate with the residuals from the
Color-Magnitude relation. Thus for spirals in clusters, we see a systematic
variation in the luminosity-weighted mean properties of the stellar populations
with central velocity dispersion. If this is a relative age trend, then
luminosity-weighted age is positively correlated with dispersion. [abridged
version]

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The categories of this paper are: math
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The categories of this paper are: stat
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The categories of this paper are: bayes-an
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The categories of this paper are: nlin
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The categories of this paper are: nucl-th
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The categories of this paper are: gr-qc
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The categories of this paper are: solv-int
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The categories of this paper are: cs
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The categories of this paper are: q-alg
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The categories of this paper are: math-ph
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The categories of this paper are: econ
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ex
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The categories of this paper are: ao-sci