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Evidence for orbital motion of material close to the central black hole of Mrk 766

Astronomy and Astrophysics 445 (2006) 59-67

Authors:

L Miller, Turner, T.J., George, I.M., Reeves, J.N.

The 2dF QSO redshift survey-XV. Correlation analysis of redshift-space distortions

Monthly Notices of the Royal Astronomical Society 360:3 (2005) 1040-1054

Authors:

J Da Ângela, PJ Outram, T Shanks, BJ Boyle, SM Croom, NS Loaring, L Miller, RJ Smith

Abstract:

We analyse the redshift-space (z-space) distortions of quasi-stellar object (QSO) clustering in the 2-degree field instrument (2dF) QSO Redshift Survey (2QZ). To interpret the z-space correlation function, ξ(σ, π), we require an accurate model for the QSO real-space correlation function, ξ(r). Although a single power-law ξ(r) ξ r-γ model fits the projected correlation function [wp(σ)] at small scales, it implies somewhat too shallow a slope for both wp(σ) and the z-space correlation function, ξ(s), at larger scales (≳20 h-1 Mpc). Motivated by the form for ξ(r) seen in the 2dF Galaxy Redshift Survey (2dFGRS) and in standard A cold dark matter (COM) predictions, we use a double power-law model for ξ(r), which gives a good fit to ξ(s) and w p(σ). The model is parametrized by a slope of γ = 1.45 for 1 < r < 10 h-1 Mpc and γ = 2.30 for 10 < r < 40 h-1 Mpc. As found for the 2dFGRS, the value of β determined from the ratio of ξ(s)/ξ(r) depends sensitively on the form of ξ(r) assumed. With our double power-law form for ξ(r), we measure β(z = 1.4) = 0.32-0.11+0.09. Assuming the same model for ξ(r), we then analyse the z-space distortions in the 2QZ ξ(σ, π) and put constraints on the values of Ωm0 and β(z = 1.4), using an improved version of the method of Hoyle et al. The constraints we derive are Ωm0 = 0.35-0.13+0.19, β(z = 1.4) = 0.50-0.15+0.13 in agreement with our ξ(s)/ξ(r) results at the ∼1σ level. © 2005 RAS.

The 2dF QSO Redshift Survey - III. The input catalogue

Monthly Notices of the Royal Astronomical Society 359:1 (2005) 57-72

Authors:

RJ Smith, SM Croom, BJ Boyle, T Shanks, L Miller, NS Loaring

Abstract:

The 2dF QSO Redshift Survey (2QZ) has obtained redshifts for in excess of 23 000 QSOs selected by their u′, bJ, r colours using the 2-degree Field (2dF) facility at the Anglo-Australian Telescope (AAT). In this paper, we describe the creation of the input catalogue from UK Schmidt photographic plates. All the plate materials used are described along with the techniques developed for flat-fielding variations in the photometric response of photographic emulsions. The selection criteria used for the survey are defined and their rationale discussed. Finally, several simple astrometric and photometric tests are performed. These demonstrate that, over the majority of the parameter space covered by this survey (18.25

The 2dF-SDSS LRG and QSO Survey: The z<2.1 Quasar Luminosity Function from 5645 Quasars to g=21.85

ArXiv astro-ph/0504300 (2005)

Authors:

GT Richards, SM Croom, SF Anderson, J Bland-Hawthorn, BJ Boyle, R De Propris, MJ Drinkwater, X Fan, JE Gunn, Z Ivezic, S Jester, J Loveday, A Meiksin, L Miller, A Myers, RC Nichol, PJ Outram, KA Pimbblet, IG Roseboom, N Ross, DP Schneider, T Shanks, RG Sharp, C Stoughton, MA Strauss, AS Szalay, DE Vanden Berk, DG York

Abstract:

We have used the 2dF instrument on the AAT to obtain redshifts of a sample of z<3, 18.021 deep surveys. The 2SLAQ data exhibit no well defined ``break'' but do clearly flatten with increasing magnitude. The shape of the quasar luminosity function derived from 2SLAQ is in good agreement with that derived from type I quasars found in hard X-ray surveys. [Abridged]

On Statistical Lensing and the Anti-Correlation Between 2dF QSOs and Foreground Galaxies

ArXiv astro-ph/0502481 (2005)

Authors:

AD Myers, PJ Outram, T Shanks, BJ Boyle, SM Croom, NS Loaring, L Miller, RJ Smith

Abstract:

We cross-correlate APM and SDSS galaxies with background QSOs from the 2dF QSO Redshift Survey, and detect a significant (2.8sigma) anti-correlation. The lack of a signal between 2dF stars and our galaxy samples suggests the anti-correlation is not due to a systematic error. The possibility that dust in the foreground galaxies could produce the anti-correlation is marginally rejected, at the 2sigma level through consideration of QSO colours. It is possible that dust that obscures QSOs without reddening them, or preferentially discards reddened QSOs from the 2QZ sample, could produce such an anti-correlation, however, such models are at odds with the positive QSO-galaxy correlations found at bright magnitudes by other authors. Our detection of a galaxy-QSO anti-correlation is consistent with statistical lensing theory. When combined with earlier results that have reported a positive galaxy-QSO correlation, a consistent, compelling picture emerges that spans faint and bright QSO samples showing positive or negative correlations according to the QSO N(m) slope. We find that galaxies are highly anti-biased on small scales. We consider two models that use different descriptions of the lensing matter and find they yield consistent predictions for the strength of galaxy bias on 0.1Mpc/h scales of b~0.1 (for LCDM). Whilst the slope of our power-law fit to the QSO-galaxy cross-correlation does not rule out linear bias, when we compare our measurement of b on 100 kpc/h scales to independent methods that determine b~1 on Mpc/h scales, we conclude that bias, on these small scales, is scale-dependent. These results indicate more mass, at least on the 100 kpc/h scales probed, than predicted by simple LCDM biasing prescriptions, and can thus constrain halo occupation models of the galaxy distribution.