Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Strong MgII Absorption Systems in QSOs from the Sloan Digital Sky Survey
  Early Data Release   We have constructed samples of low-ionization metal absorption-line systems
selected for the strength of their MgII lambda2796 lines from the SDSS EDR.
There are 640 absorption systems in our unbiased sample with lambda2796 REW >
1.0 A detected at 5 sigma and with redshifts 0.37 < z < 2.27. This sample is an
order of magnitude larger than previous similarly selected samples. In this
contribution, we present preliminary results on the statistical properties of
the sample.

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The categories of this paper are: gr-qc
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The categories of this paper are: econ
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The categories of this paper are: plasm-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: physics
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: supr-con
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The categories of this paper are: ao-sci
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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: adap-org
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-th