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Related papers: Sample Variance Considerations for Cluster Surveys

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We study the dependence of galaxy clustering on luminosity and stellar mass at redshifts z ~ [0.2-1] using the first zCOSMOS 10K sample. We measure the redshift-space correlation functions xi(rp,pi) and its projection wp(rp) for sub-samples…

We analyse parallel N-body simulations of three Cold Dark Matter (CDM) universes to study the abundance and clustering of galaxy clusters. The simulations cover a volume comparable to the forthcoming SDSS. We are able to make robust…

Astrophysics · Physics 2008-11-26 F. Governato , A. Babul , T. Quinn , P. Tozzi , C. M. Baugh , N. Katz , G. Lake

Galaxy cluster surveys are power tools for studying the dark energy. In principle, the equation of state parameter w of the dark energy and its time evolution can be extracted from large solid angle, high yield surveys that deliver tens of…

Astrophysics · Physics 2007-05-23 Joseph J Mohr

Photometric galaxy surveys probe the late-time Universe where the density field is highly non-Gaussian. A consequence is the emergence of the super-sample covariance (SSC), a non-Gaussian covariance term that is sensitive to fluctuations on…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-23 S. Gouyou Beauchamps , F. Lacasa , I. Tutusaus , M. Aubert , P. Baratta , A. Gorce , Z. Sakr

We present a new method aiming to simplify the cosmological analysis of X-ray cluster surveys. It is based on purely instrumental observable quantities, considered in a two-dimensional X-ray colour-magnitude diagram (hardness ratio versus…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Nicolas Clerc , Marguerite Pierre , Florian Pacaud , Tatyana Sadibekova

The clustering of galaxies in ongoing and upcoming galaxy surveys contains a wealth of cosmological information, but extracting this information is a non-trivial task since galaxies and their host haloes are stochastic tracers of the matter…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 Tobias Baldauf , Uroš Seljak , Robert E. Smith , Nico Hamaus , Vincent Desjacques

With the advent of large-scale weak lensing surveys there is a need to understand how realistic, scale-dependent systematics bias cosmic shear and dark energy measurements, and how they can be removed. Here we describe how spatial…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-31 A. N. Taylor , T. D. Kitching

Data analysis from upcoming large galaxy redshift surveys, such as Euclid and DESI will significantly improve constraints on cosmological parameters. To optimally extract the information from these galaxy surveys, it is important to control…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-22 S. Gouyou Beauchamps , P. Baratta , S. Escoffier , W. Gillard , J. Bel , J. Bautista , C. Carbone

[abridged] We present a first cosmological analysis of a refined cluster catalog from the Red-Sequence Cluster Survey (RCS). The input cluster sample is derived from 72.07 square degrees of imaging data [...] The catalog contains 956…

We construct a family of simple analytical models of galaxy clusters at the present epoch and compare its predictions with observational data. We explore two processes that break the self-similarity of galaxy clusters: systematic variation…

Astrophysics · Physics 2007-05-23 E. J. Lloyd-Davies , R. G. Bower , T. J. Ponman

When Cold Dark Matter (CDM) power spectrum normalized by COBE results, its amplitude at smaller scales can be parametrized by $\Gamma\sim\Omega_0h$. The expected variations of Hubble flows in two samples, the sample of 36 clusters in the…

Astrophysics · Physics 2016-01-13 Xiangdong Shi

Results of a study of the theoretically predicted and observed X-ray properties of local massive star clusters are presented, with a focus on understanding the mass and energy flow from these clusters into the ISM via a cluster wind. A…

Astrophysics · Physics 2009-11-07 Ian R. Stevens , Joanna M. Hartwell

Galaxy cluster surveys provide a powerful means of studying the density and nature of the dark energy. The redshift distribution of detected clusters in a deep, large solid angle SZE or X-ray survey is highly sensitive to the dark energy…

Astrophysics · Physics 2009-11-07 Joseph J. Mohr , Brian OShea , August E. Evrard , John Bialek , Zoltan Haiman

The number density of galaxy clusters provides tight statistical constraints on the matter fluctuation power spectrum normalization, traditionally phrased in terms of sigma_8, the root mean square mass fluctuation in spheres with radius 8…

Astrophysics · Physics 2011-02-11 J. Patrick Henry , August E. Evrard , Henk Hoekstra , Arif Babul , Andishieh Mahdavi

We give a summary of recent results on spatial and velocity biases in cosmological models. Progress in numerical techniques made it possible to simulate halos in large volumes with a such accuracy that halos survive in dense environments of…

Astrophysics · Physics 2007-05-23 Anatoly Klypin

In the standard Lambda CDM cosmological model with a Gaussian primordial density fluctuation field, the relatively low value of the mass variance parameter (sigma_8=0.74{+0.05}{-0.06}, obtained from the WMAP 3-year data) results in a…

Astrophysics · Physics 2009-06-23 S. Sadeh , Y. Rephaeli , J. Silk

(abridged) We use a theoretical model to predict the clustering properties of galaxy clusters. Our technique accounts for past light-cone effects on the observed clustering and follows the non-linear evolution of the dark matter correlation…

Astrophysics · Physics 2009-10-31 Lauro Moscardini , Sabino Matarrese , H. J. Mo

Scaling relations of observed galaxy cluster properties are useful tools for constraining cosmological parameters as well as cluster formation histories. One of the key cosmological parameters, sigma8, is constrained using observed clusters…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-19 Julia M. Comerford , Leonidas A. Moustakas , Priyamvada Natarajan

We investigate the impact of beam chromaticity, i.e., the frequency dependence of the beam window function, on cosmological and astrophysical parameter constraints from CMB power spectrum observations. We show that for future…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-18 S. Giardiello , A. J. Duivenvoorden , E. Calabrese , G. Galloni , M. Hasselfield , J. C. Hill , A. La Posta , T. Louis , M. Madhavacheril , L. Pagano

We study the effects of sample variance in N--body simulations, as a function of the size of the simulation box, namely in connection with predictions on tomographic shear spectra. We make use of a set of 8 $\Lambda$CDM simulations in boxes…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-20 Luciano Casarini , Oliver Piattella , Silvio Bonometto , Marino Mezzetti
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