Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The luminosity dependence of the Type 1 AGN fraction   Using a complete, magnitude-limited sample of active galaxies from the Sloan
Digital Sky Survey (SDSS) we show that the fraction of broad-line (Type 1)
active galactic nuclei increases with luminosity of the isotropically-emitted
[O III] narrow emission line. Our results are quantitatively in agreement with,
and far less uncertain than, similar trends found from studies of X-ray and
radio-selected active galaxies. While the correlation between broad-line
fraction and luminosity is qualitatively consistent with the receding torus
model, its slope is shallower and we therefore propose a modification to this
model where the height of the torus increases slowly with AGN luminosity. We
demonstrate that the faint-end slope of the AGN luminosity function steepens
significantly when a correction for `missing' Type 2 objects is made and that
this can substantially affect the overall AGN luminosity density extrapolated
from samples of more luminous objects.

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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: hep-lat
3
The categories of this paper are: physics
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The categories of this paper are: q-alg
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The categories of this paper are: comp-gas
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The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
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The categories of this paper are: hep-th
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The categories of this paper are: nucl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: econ
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The categories of this paper are: quant-ph
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: cmp-lg