Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Stromgren Photometry from z=0 to z~1. The Method   We use rest-frame Stromgren photometry to observe clusters of galaxies in a
self-consistent manner from z=0 to z=0.8. Stromgren photometry of galaxies is
an efficient compromise between standard broad-band photometry and
spectroscopy, in the sense that it is more sensitive to subtle variations in
spectral energy distributions than the former, yet much less time-consuming
than the latter. Principal Component Analysis (PCA) is used to extract maximum
information from the Stromgren data. By calibrating the Principal Components
using well-studied galaxies (and stellar population models), we develop a
purely empirical method to detect, and subsequently classify, cluster galaxies
at all redshifts smaller than 0.8. Interlopers are discarded with unprecedented
efficiency (up to 100%). The first Principal Component essentially reproduces
the Hubble Sequence, and can thus be used to determine the global star
formation history of cluster members. The (PC2, PC3) plane allows us to
identify Seyfert galaxies (and distinguish them from starbursts) based on
photometric colors alone. In the case of E/S0 galaxies with known redshift, we
are able to resolve the age-dust- metallicity degeneracy, albeit at the
accuracy limit of our present observations. This technique will allow us to
probe galaxy clusters well beyond their cores and to fainter magnitudes than
spectroscopy can achieve. We are able to directly compare these data over the
entire redshift range without a priori assumptions because our observations do
not require k-corrections. The compilation of such data for different cluster
types over a wide redshift range is likely to set important constraints on the
evolution of galaxies and on the clustering process.

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The categories of this paper are: acc-phys
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The categories of this paper are: stat
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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-th
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The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
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The categories of this paper are: patt-sol
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The categories of this paper are: solv-int
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The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: dg-ga
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The categories of this paper are: eess
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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-ex