Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Breaking the sigma_8-Omega_m degeneracy using the clustering of high-z
  X-ray AGN   The clustering of X-ray selected AGN appears to be a valuable tool for
extracting cosmological information. Using the recent high-precision angular
clustering results of ~30000 XMM-Newton soft (0.5-2 keV) X-ray sources (Ebrero
et al. 2009), which have a median redshift of $z\sim 1$, and assuming a flat
geometry, a constant in comoving coordinates AGN clustering evolution and the
AGN bias evolution model of Basilakos et al. (2008), we manage to break the
Omega_m-sigma_8 degeneracy. The resulting cosmological constraints are:
Omega_m=0.27 (+0.03 -0.05), w=-0.90 (+0.10 -0.16) and sigma_8=0.74 (+0.14
-0.12), while the dark matter host halo mass, in which the X-ray selected AGN
are presumed to reside, is M=2.50 (+0.50 -1.50) X 10^13 h^{-1} M(solar). For
the constant Lambda model (w=-1) we find Omega_m=0.24 (+- 0.06) and
sigma_8=0.83 (+0.11 -0.16), in good agreement with recent studies based on
cluster abundances, weak lensing and the CMB, but in disagreement with the
recent bulk flow analysis.

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The categories of this paper are: hep-th
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The categories of this paper are: eess
28
The categories of this paper are: alg-geom
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The categories of this paper are: supr-con
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The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin
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The categories of this paper are: acc-phys
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The categories of this paper are: math
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The categories of this paper are: nlin
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The categories of this paper are: plasm-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: stat