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We present a power spectrum analysis of the final 2dF Galaxy Redshift Survey, employing a direct Fourier method. The sample used comprises 221,414 galaxies with measured redshifts. We investigate in detail the modelling of the sample…

We use the 2dF Galaxy Redshift Survey data to compile catalogues of superclusters for the Northern and Southern regions of the 2dFGRS, altogether 543 superclusters at redshifts 0.009 < z < 0.2. We analyse methods of compiling supercluster…

We present a robust method to estimate the redshift of galaxies using Pan-STARRS1 photometric data. Our method is an adaptation of the one proposed by Beck et al. (2016) for the SDSS Data Release 12. It uses a training set of 2313724…

Astrophysics of Galaxies · Physics 2020-10-14 Paula Tarrío , Stefano Zarattini

It is difficult to accurately identify galaxy mergers and it is an even larger challenge to classify them by their mass ratio or merger stage. In previous work we used a suite of simulated mergers to create a classification technique that…

Astrophysics of Galaxies · Physics 2023-04-12 R. Nevin , L. Blecha , J. Comerford , J. Simon , B. A. Terrazas , R. S. Barrows , J. A. Vázquez-Mata

We develop new methods to study the properties of galaxy redshift surveys and radial peculiar velocity surveys, both individually and combined. We derive the Fisher information matrix for redshift surveys, including redshift distortions and…

Astrophysics · Physics 2009-11-10 Daniel Burkey , Andy Taylor

We present a method for automated classification of galaxies with low signal-to-noise (S/N) spectra typical of redshift surveys. We develop spectral simulations based on the parameters for the 2dF Galaxy Redshift Survey, and with these…

Astrophysics · Physics 2015-06-24 S. R. Folkes , O. Lahav , S. J. Maddox

I review the status of large-scale structure studies based on redshift surveys of galaxies and clusters of galaxies. In particular, I compare recent results on the power spectrum and two-point correlation correlation function from the 2dF…

Astrophysics · Physics 2007-05-23 L. Guzzo

We review cosmological inference from galaxy surveys at low and high redshifts, with emphasis on new Southern sky surveys. We focus on several issues: (i) The importance of understanding selection effects in catalogues and matching Northern…

Astrophysics · Physics 2007-05-23 Ofer Lahav

Galaxy redshift surveys are one of the key probes in modern cosmology. In the data analysis of galaxy surveys, the precision of the statistical measurement is primarily limited by the cosmic variance on large scales. Fortunately, this…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-27 Yuting Wang , Gong-Bo Zhao

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

Photometric redshifts (photo-z's) are fundamental in galaxy surveys to address different topics, from gravitational lensing and dark matter distribution to galaxy evolution. The Kilo Degree Survey (KiDS), i.e. the ESO public survey on the…

The 2dF Galaxy Redshift Survey is the first to measure more than 100,000 redshifts. This allows precise measurements of many of the key statistical measures of galaxy clustering, in particular redshift-space distortions and the large-scale…

Astrophysics · Physics 2009-11-06 J. A. Peacock , the 2dFGRS Team

We present a photometric method for identifying stars, galaxies and quasars in multi-color surveys, which uses a library of >65000 color templates. The method aims for extracting the information content of object colors in a statistically…

Astrophysics · Physics 2009-06-16 C. Wolf , K. Meisenheimer , H. -J. Röser

The 2dF Galaxy Redshift Survey is the first to observe more than 100,000 redshifts, making possible precise measurements of many aspects of galaxy clustering. The spatial distribution of galaxies can be studied as a function of galaxy…

Astrophysics · Physics 2009-11-07 J. A. Peacock

The 2dF Galaxy Redshift Survey is a major new initiative to map a representative volume of the universe. The survey makes use of the 2dF multi-fibre spectrograph at the Anglo-Australian Telescope to measure redshifts for over 250,000…

Astrophysics · Physics 2009-10-30 Matthew Colless

We present a new non-parametric method to quantify morphologies of galaxies based on a particular family of learning machines called support vector machines. The method, that can be seen as a generalization of the classical CAS…

Astrophysics · Physics 2009-11-13 M. Huertas-Company , D. Rouan , L. Tasca , G. Soucail , O. Le Fevre

The 100,000 spectra from the 2 degree Field Galaxy Redshift Survey (2dFGRS) in the 100k Public Data Release represent the largest single compilation of galaxy spectra available. By virtue of its sheer size and the properties of the…

Astrophysics · Physics 2009-11-07 Darren S. Madgwick , Paul C. Hewett , Daniel J. Mortlock , Ofer Lahav

Accurate and automated galaxy redshift determination is essential for maximizing the scientific return of spectroscopic surveys. In this paper, we propose a data-driven method to address this challenge. The method first learns a rest-frame…

Instrumentation and Methods for Astrophysics · Physics 2026-05-13 Masten Bourahma , Nicolas F. Bouché , Roland Bacon , Johan Richard , Tanya Urrutia , Afonso Vale , Martin Wendt , T. T. Thai

We describe and apply a simple prescription for defining connected structures in galaxy redshift surveys. The method is based upon two passes with a friends-of-friends groupfinder. The first pass uses a cylindrical linking volume to find…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-12 David N. A. Murphy , Vincent R. Eke , Carlos S. Frenk

The recently initiated SPHEREx and 7DS surveys will deliver low-resolution spectra ($R\approx 30-130$) for hundreds of millions of galaxies over the optical to near-infrared range ($0.4-5.0\mu m$), covering a wide sky area without sample…