Abstract
We present a new redshift survey, the 2dF Quasar Dark Energy Survey pilot
(2QDESp), which consists of $\approx10000$ quasars from $\approx150$
deg$^2$ of the southern sky, based on VST-ATLAS imaging and 2dF/AAOmega
spectroscopy. Combining our optical photometry with the WISE (W1,W2) bands we
can select essentially contamination free quasar samples with $0.8<z<2.5$
and $g<20.5$. At fainter magnitudes, optical UVX selection is still required
to reach our $g\approx22.5$ limit. Using both these techniques we observed
quasar redshifts at sky densities up to $90$ deg$^-2$. By comparing 2QDESp
with other surveys (SDSS, 2QZ and 2SLAQ) we find that quasar clustering is
approximately luminosity independent, with results for all four surveys
consistent with a correlation scale of $r_0=6.1\pm0.1 \: h^-1$Mpc,
despite their decade range in luminosity. We find a significant redshift
dependence of clustering, particularly when BOSS data with $r_0=7.3\pm0.1
\: h^-1$Mpc are included at $z\approx2.4$. All quasars remain consistent
with having a single host halo mass of $\approx2\pm1\times10^12 \:
h^-1M_ødot$. This result implies that either quasars do not radiate at a
fixed fraction of the Eddington luminosity or AGN black hole and dark matter
halo masses are weakly correlated. No significant evidence is found to support
fainter, X-ray selected quasars at low redshift having larger halo masses as
predicted by the `hot halo' mode AGN model of Fanidakis et al. 2013. Finally,
although the combined quasar sample reaches an effective volume as large as
that of the original SDSS LRG sample, we do not detect the BAO feature in these
data.
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