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Related papers: Reconstructing PSCz with a Generalised PIZA

200 papers

We present photometric redshifts (photo-$z$) for the deep wide fields of the Physics of the Accelerating Universe Survey (PAUS), covering an area of $\sim$50 deg$^{2}$, for $\sim$1.8 million objects up to $i_{\textrm{AB}}<23$. The PAUS deep…

We present a photometric redshift (photo-$z$) estimation technique for galaxies in the P\lowercase{an}-STARRS1 (PS1) $3\pi $ survey. Specifically, we train and test a regression and a classification Random-Forest (RF) models using…

Astrophysics of Galaxies · Physics 2021-05-28 A. Baldeschi , M. Stroh , R. Margutti , T. Laskar , A. Miller

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…

We present a new method for recovering the cosmological density, velocity, and potential fields from all-sky redshift catalogues. The method is based on an expansion of the fields in orthogonal radial (Bessel) and angular (spherical…

Astrophysics · Physics 2015-06-24 Karl Fisher , Ofer Lahav , Yehuda Hoffman , Donald Lynden-Bell , Saleem Zaroubi

We describe the Carnegie-Spitzer-IMACS (CSI) Survey, a wide-field, near-IR selected spectrophotometric redshift survey with IMACS on Magellan-Baade. CSI uses a flux-limited sample of galaxies in Spitzer IRAC 3.6micron imaging of SWIRE…

Peculiar velocities of galaxies and halos can be reconstructed from their spatial distribution alone. This technique is analogous to the baryon acoustic oscillations (BAO) reconstruction, using the continuity equation to connect density and…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-24 Bernardita Ried Guachalla , Emmanuel Schaan , Boryana Hadzhiyska , Simone Ferraro

We present ZEBRA, the Zurich Extragalactic Bayesian Redshift Analyzer. The current version of ZEBRA combines and extends several of the classical approaches to produce accurate photometric redshifts down to faint magnitudes. In particular,…

We apply the ZTRACE algorithm to the optical NOG and infra-red PSCz galaxy catalogues to reconstruct the pattern of primordial fluctuations that have generated our local Universe. We check that the density fields traced by the two…

Astrophysics · Physics 2009-11-07 Fabio Fontanot , Pierluigi Monaco , Stefano Borgani

We show how to enhance the redshift accuracy of surveys consisting of tracers with highly uncertain positions along the line of sight. Photometric surveys with redshift uncertainty delta_z ~ 0.03 can yield final redshift uncertainties of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jens Jasche , Benjamin D. Wandelt

Peculiar motion introduces systematic variations in the observed luminosity distribution of galaxies. This allows one to constrain the cosmic peculiar velocity field from large galaxy redshift surveys. Using around half a million galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-19 Martin Feix , Adi Nusser , Enzo Branchini

We present an analytic method for rapidly forecasting the accuracy of gravitational potential reconstruction possible from measurement of radial peculiar velocities of every galaxy cluster with M > M_th in solid angle \theta^2 and over…

Astrophysics · Physics 2009-11-07 Olivier Doré , Lloyd Knox , Alan Peel

We have used the two IRAS redshift surveys, 1.2-Jy (Fisher et al 1995) and PSCz (Saunders et al 2000), to model the linear velocity fields within a redshift of 8,000 km/s and have compared them in redshift space. The two velocity fields…

Astrophysics · Physics 2007-05-23 Luis Teodoro , Enzo Branchini , Carlos Frenk

We study the performance of the hybrid template-machine-learning photometric redshift (photo-$z$) algorithm Delight, which uses Gaussian processes, on a subset of the early data release of the Physics of the Accelerating Universe Survey…

We derive peculiar velocities for the 6dF Galaxy Survey (6dFGS) and describe the velocity field of the nearby ($z<0.055$) southern hemisphere. The survey comprises 8885 galaxies for which we have previously reported Fundamental Plane data.…

Recent Lyman-$\alpha$ forest tomography measurements of the intergalactic medium (IGM) have revealed a wealth of cosmic structures at high redshift ($z\sim 2.5$). In this work, we present the Tomographic Absorption Reconstruction and…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-18 Benjamin Horowitz , Khee-Gan Lee , Martin White , Alex Krolewski , Metin Ata

We describe an algorithm to detect voids in galaxy redshift surveys. The method is based on the void finder algorithm of El-Ad & Piran. We apply a series of tests to determine how accurately we are able to recover the volumes of voids using…

Astrophysics · Physics 2008-12-18 Fiona Hoyle , Michael S. Vogeley

The Laniakea Supercluster is the closest large scale structure of galaxies. Is such a structure expected in the standard cold dark matter model of cosmology? This would be a relatively simple question to answer, were it not for the fact…

Astrophysics of Galaxies · Physics 2026-05-26 Jeremy Mould , Helene M. Courtois , Renee C. Kraan-Korteweg , Amber Hollinger

We utilise the method of Wiener reconstruction with spherical harmonics and Bessel functions to recover the density and velocity fields from the IRAS 1.2Jy redshift survey. The results are robust to changes in prior parameters and the…

Astrophysics · Physics 2015-06-24 Matthew Webster , Ofer Lahav , Karl Fisher

In addition to the intrinsic clustering of galaxies themselves, the spatial distribution of galaxies observed in surveys is modulated by the presence of weak lensing due to matter in the foreground. This effect, known as magnification bias,…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-09 Lukas Wenzl , Shi-Fan Chen , Rachel Bean

Systematic surveys are being proposed to discover a significant number of galaxies at z ~ 6, which is now suggested as the epoch when the reionization era of the Universe ends. To plan such surveys, we need a reasonable expectation of the…