Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The z=5.8 Quasar SDSSp J1044-0125: A Peek at Quasar Evolution?   The newly discovered z=5.8 quasar SDSSp J104433.04-012502.2 was recently
detected in X-rays and found to be extremely X-ray weak. Here we present the
hardness ratio analysis of the XMM-Newton observation. We consider various
models to explain the detection in the soft X-ray band and non-detection in the
hard band, together with its X-ray weakness. We show that the source may have a
steep power-law slope, with an absorber partially covering the continuum. This
may be X-ray evidence to support the argument of Mathur (2000) that narrow line
Seyfert 1 galaxies, which show steep power-law slopes, might be the low
redshift, low luminosity analogues of the high redshift quasars. Heavily
shrouded and steep X-ray spectrum quasars may indeed represent the early stages
of quasar evolution (Mathur 2000, Fabian 1999) and SDSSp J104433.04-012502.2 is
possibly giving us a first glimpse of the physical evolution of quasar
properties.

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The categories of this paper are: plasm-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: q-alg
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The categories of this paper are: math-ph
2
The categories of this paper are: math
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The categories of this paper are: eess
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The categories of this paper are: stat
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The categories of this paper are: cmp-lg
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-bio
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-lat
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The categories of this paper are: nlin
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The categories of this paper are: patt-sol