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Related papers: Sampling Effects on Cosmological Dipoles

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Galaxy cluster masses, rich with cosmological information, can be estimated from internal dark matter (DM) velocity dispersions, which in turn can be observationally inferred from satellite galaxy velocities. However, galaxies are biased…

Large ongoing and upcoming galaxy cluster surveys in the optical, X-ray and millimetric wavelengths will provide rich samples of galaxy clusters at unprecedented depths. One key observable for constraining cosmological models is the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Patrick Valageas , Nicolas Clerc

Comparison of peculiar velocities of galaxies with their gravitational accelerations (induced by the density field) is one of the methods to constrain the redshift distortion parameter \beta=(\Omega_m^0.55)/b, where \Omega_m is the…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-17 Maciej Bilicki , Michał Chodorowski , Wojciech Hellwing , Thomas Jarrett , Gary Mamon

Spatial intensity moments computed on images can be used as a probe of the centroid, size, and orientation of pixelized sources such as stars and galaxies. However, all measurements made on images suffer from errors due to undersampling and…

Instrumentation and Methods for Astrophysics · Physics 2020-12-11 Andrew K. Bradshaw

Galaxies are arranged in interconnected walls and filaments forming a cosmic web encompassing huge, nearly empty, regions between the structures. Many statistical methods have been proposed in the past in order to describe the galaxy…

Astrophysics · Physics 2016-02-17 J-L. Starck , V. J. Martinez , D. L. Donoho , O. Levi , P. Querre , E. Saar

This article is the second in a series in which we perform an extensive comparison of various galaxy-based cluster mass estimation techniques that utilise the positions, velocities and colours of galaxies. Our aim is to quantify the…

I review recent progress in understanding and modeling galaxy clustering in cosmological simulations, with emphasis on models based on high-resolution dissipationless simulations. During the last decade, significant advances in our…

Astrophysics · Physics 2007-05-23 Andrey V. Kravtsov

This paper examines several methods of tracing galaxies in N-body simulations and their effects on the derived galaxy statistics, especially measurements of velocity bias. Using two simulations with identical initial conditions, one…

Astrophysics · Physics 2009-06-16 F J Summers , Marc Davis , August E. Evrard

Realistic lightcone mocks are important in the clustering analyses of large galaxy surveys. For simulations where only the snapshots are available, it is common to create approximate lightcones by joining together the snapshots in spherical…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-02 Alex Smith , Shaun Cole , Cameron Grove , Peder Norberg , Pauline Zarrouk

We study the redshift space correlation function of galaxy clusters for observational samples constructed in different surveys. We explore correlation amplitudes, pairwise velocity distributions and bias factors. Systematics in cluster…

Astrophysics · Physics 2009-11-07 N. D. Padilla , D. G. Lambas

We estimate the dipole of the whole sky X-ray flux-limited sample of Abell/ACO clusters (XBACs) and compare it to the optical Abell/ACO cluster dipole. The X-ray cluster dipole is well aligned ($\le 25^{\circ}$) with the CMB dipole, while…

Astrophysics · Physics 2009-10-30 M. Plionis , E. Kolokotronis

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

One of the main problems in the studies of large scale galaxy structures concerns the relation of the correlation properties of a certain population of objects with those of a selected subsample of it, when the selection is performed by…

Astrophysics · Physics 2007-05-23 Francesco Sylos Labini

We study the linear and non-linear bias parameters which determine the mapping between the distributions of galaxies and the full matter density fields, comparing different measurements and predictions. Associating galaxies with dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-21 Kai Hoffmann , Julien Bel , Enrique Gaztanaga

General relativistic effects have long been predicted to subtly influence the observed large-scale structure of the universe. The current generation of galaxy redshift surveys have reached a size where detection of such effects is becoming…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-25 Shadab Alam , Hongyu Zhu , Rupert A. C. Croft , Shirley Ho , Elena Giusarma , Donald P. Schneider

We present a comparative analysis of estimators and Bayesian methods for determining the number count dipole from cosmological surveys. The increase in discordance between the number count dipole and the CMB's kinematic dipole has presented…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-30 Vasudev Mittal , Oliver T. Oayda , Geraint F. Lewis

The exploitation of clusters of galaxies as cosmological probes relies on accurate measurements of their total gravitating mass. X-ray observations provide a powerful means of probing the total mass distribution in galaxy clusters, but…

Astrophysics · Physics 2009-11-13 Rocco Piffaretti , Riccardo Valdarnini

We use a suite of high-resolution cosmological dwarf galaxy simulations to test the accuracy of commonly-used mass estimators from Walker et al.(2009) and Wolf et al.(2010), both of which depend on the observed line-of-sight velocity…

We have used a statistical technique "Shuffle" (Bhavsar & Ling 1988; Bharadwaj, Bhavsar & Sheth 2004) in seven nearly two dimensional strips from the Sloan Digital Sky Survey Data Release Six (SDSS DR6) to test if the statistically…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-28 Biswajit Pandey

[Abridged] We present an analysis of the relation between the masses of cluster- and group-sized halos, extracted from $\Lambda$CDM cosmological N-body and hydrodynamic simulations, and their velocity dispersions, at different redshifts…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-04 Emiliano Munari , Andrea Biviano , Stefano Borgani , Giuseppe Murante , Dunja Fabjan