English
Related papers

Related papers: The 2dF QSO Redshift Survey - 10K@2K!

200 papers

We have run Monte Carlo simulations, for quasar clustering redshift distortions in the Two-Degree Field QSO Redshift Survey (2QZ), in order to elicit the power of redshift distortions (geometric Alcock-Paczynski and linear kinematic) to…

Astrophysics · Physics 2007-05-23 M. O. Calvao , J. R. T de Mello Neto , I. Waga

Since the late 1970's, redshift surveys have been vital for progress in understanding large-scale structure in the Universe. The original CfA redshift survey collected spectra of 20-30 galaxies per clear night on a 1.5 meter telescope; over…

Astrophysics · Physics 2009-11-06 Marc Davis , Jeffrey Newman

Using ~300,000 photometrically classified quasars, by far the largest quasar sample ever used for such analyses, we study the redshift and luminosity evolution of quasar clustering on scales of ~50 kpc/h to ~20 Mpc/h from redshifts of…

The 2dF Galaxy Redshift Survey (2dFGRS) of 230,000 redshifts of nearby (z~0.1) galaxies is now complete. It has allowed the 2dFGRS team and others to estimate fundamental cosmological parameters and to study galaxy intrinsic properties.…

Astrophysics · Physics 2009-11-10 Ofer Lahav

The technique of estimating redshifts using photometric rather than spectroscopic observations has recently received great attention due to its simplicity and the accuracy of the results obtained. In this work, we estimate photometric…

Astrophysics · Physics 2007-05-23 S. Kitsionas , E. Hatziminaoglou , I. Georgantopoulos , A. Georgakakis , O. Giannakis

We optimize the design of future spectroscopic redshift surveys for constraining the dark energy via precision measurements of the baryon acoustic oscillations (BAO), with particular emphasis on the design of the Wide-Field Multi-Object…

In the near future, new surveys promise a significant increase in the number of quasars (QSO) at large redshifts. This will help to constrain the dark energy models using quasars. The Large Synoptic Survey Telescope (LSST) will cover over…

Astrophysics of Galaxies · Physics 2019-10-08 Mary Loli Martínez-Aldama , Swayamtrupta Panda , Bożena Czerny , Michal Zajaček

We determine the number counts and z=0-5 luminosity function for a well-defined, homogeneous sample of quasars from the Sloan Digital Sky Survey (SDSS). We conservatively define the most uniform statistical sample possible, consisting of…

Machine learning techniques, specifically the k-nearest neighbour algorithm applied to optical band colours, have had some success in predicting photometric redshifts of quasi-stellar objects (QSOs): Although the mean of differences between…

Instrumentation and Methods for Astrophysics · Physics 2020-01-29 S. J. Curran

The evolution of QSO clustering is investigated with a new sample of 388 QSOs with 0.3<z<2.2, B<20.5 and M_B<-23. Evidence is found for an increase of the clustering amplitude with increasing redshift. These measurements allow to further…

Astrophysics · Physics 2007-05-23 F. La Franca , P. Andreani , S. Cristiani

We present the power spectrum of galaxy clusters measured from the new ROSAT-ESO Flux-Limited X-Ray (REFLEX II) galaxy cluster catalogue. This new sample extends the flux limit of the original REFLEX to $1.8 \times 10^{-12} erg/ s/cm^{2}$,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 A. Balaguera-Antolinez , Ariel G. Sanchez , H. Böhringer , C. Collins , L. Guzzo , S. Phleps

We discuss cosmological inference from galaxy surveys at low and high redshifts. Studies of optical and IRAS redshift surveys with median redshift ${\bar z} \sim 0.02$ yield measurements of the density parameter $\Omega$ and the…

Astrophysics · Physics 2007-05-23 Ofer Lahav

We have used the publicly available data from the 2dF Galaxy Redshift Survey and the 2dF QSO Redshift Survey to test the hypothesis that there is a periodicity in the redshift distribution of quasi-stellar objects (QSOs) found projected…

Astrophysics · Physics 2009-11-07 E. Hawkins , S. J. Maddox , M. R. Merrifield

We use the direct Fourier method to calculate the redshift-space power spectrum of the maxBCG cluster catalog (Koester et al. 2007) -- currently by far the largest existing galaxy cluster sample. The total number of clusters used in our…

Astrophysics · Physics 2007-05-23 Gert Huetsi

The cosmic microwave background (CMB) has provided a precise template for features in the linear power spectrum: the matter-radiation turnover, sound horizon drop, and acoustic oscillations. In a two dimensional power spectrum in redshift…

Astrophysics · Physics 2008-11-26 Wayne Hu , Zoltan Haiman

The 6dF Galaxy Survey (6dFGS) aims to measure the redshifts of around 150,000 galaxies, and the peculiar velocities of a 15,000-member sub-sample, over almost the entire southern sky. When complete, it will be the largest redshift survey of…

The 2dF Galaxy Redshift Survey has now measured in excess of 160000 galaxy redshifts. This paper presents the power spectrum of the galaxy distribution, calculated using a direct FFT-based technique. We argue that, within the k-space region…

We present detailed clustering measurements for a flux limited sample of 14,000 quasars extracted from the 2dF QSO Redshift Survey (2QZ) in the redshift range 0.8<z<2.1. After splitting the sample into three redshift bins and each of them…

Astrophysics · Physics 2009-11-11 Cristiano Porciani , Peder Norberg

We have analysed the optical luminosity-redshift distribution properties of bright QSOs, using a new large sample from the Hamburg/ESO survey. The sample provides insight into the hitherto poorly sampled bright tail of the luminosity…

Astrophysics · Physics 2007-05-23 Lutz Wisotzki

We review the current status of QSO clustering measurements, particular with respect to their relevance in understanding AGN physics. Measurements based on the 2dF QSO Redshift Survey (2QZ) find a scale length for QSO clustering of…