Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evolution of the colour-magnitude relation of early-type galaxies in
  distant clusters   We present a thorough quantitative analysis of the evolution of the
colour-magnitude relation for early-type galaxies in 17 distant clusters with
redshifts 0.31 < z < 1.27 using the Kodama & Arimoto (1997) evolutionary model
for elliptical galaxies. The model is calibrated to reproduce the colour-
magnitude relation for Coma ellipticals at z ~ 0 and gives the evolution of the
slope and zero-point as a function of redshift. We find no significant
differences between the colour-magnitude relations of the clusters in our
sample. The slopes can be reproduced by a single model sequence in which all
elliptical galaxies are assumed to be equally old (the maximum age difference
allowed for the brightest 3 magnitudes is only 1 Gyr) and to have mean stellar
metallicities which vary as a function of galaxy luminosity. The zero-points of
the colour-magnitude relations constrain the epoch of major star formation in
early-type galaxies to z_f>2-4. This study provides two important constraints
for any model of the formation of rich clusters: the uniformity of the ages of
the stellar populations in the early-type galaxies and the universality of the
metallicity sequence of these galaxies as a function of galaxy mass.

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The categories of this paper are: gr-qc
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The categories of this paper are: physics
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
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The categories of this paper are: math-ph
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The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
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The categories of this paper are: hep-ph
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The categories of this paper are: supr-con
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The categories of this paper are: cond-mat
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The categories of this paper are: nlin
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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: q-fin