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Related papers: Galaxy Tracers and Velocity Bias

200 papers

By combining galaxy tracers from high-resolution N-body and hydrodynamical simulations, we present a consistent picture of the behaviour of galaxy velocities in massive clusters. In haloes above ~ 10^14 Msun, the brightest satellite…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-20 Hao-Yi Wu , Oliver Hahn , August E. Evrard , Risa H. Wechsler , Klaus Dolag

We present a simple model that accurately describes various statistical properties of peculiar velocities of dark matter halos. We pay particular attention to the following two effects; first, the evolution of the halo peculiar velocity…

Astrophysics · Physics 2009-11-07 Takashi Hamana , Issha Kayo , Naoki Yoshida , Yasushi Suto , Y. P. Jing

We use the hydrodynamical galaxy formation simulations from the Illustris suite to study the origin and properties of galaxy velocity bias, i.e., the difference between the velocity distributions of galaxies and dark matter inside halos. We…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-31 Jia-Ni Ye , Hong Guo , Zheng Zheng , Idit Zehavi

The distribution of galaxies in position and velocity around the centers of galaxy clusters encodes important information about cluster mass and structure. Using the maxBCG galaxy cluster catalog identified from imaging data obtained in the…

Cosmic voids are underdense regions within the large-scale structure of the Universe, spanning a wide range of physical scales - from a few megaparsecs (Mpc) to the largest observable structures. Their distinctive properties make them…

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 investigate the feasibility of carrying out likelihood analysis on the velocities of galaxy clusters to determine power spectrum parameters. Using N-body simulations of cosmological density fields we show that the velocity field traced…

Astrophysics · Physics 2007-05-23 Rupert Croft , George Efstathiou

We conduct gravitational microlensing experiments in a galaxy taken from a cosmological N-body simulation. Hypothetical observers measure the optical depth and event rate toward hypothetical LMCs and compare their results with model…

Astrophysics · Physics 2009-10-30 Lawrence M. Widrow , John Dubinski

We describe the astrophysical and numerical basis of N-body simulations, both of collisional stellar systems (dense star clusters and galactic centres) and collisionless stellar dynamics (galaxies and large-scale structure). We explain and…

Instrumentation and Methods for Astrophysics · Physics 2011-05-26 Walter Dehnen , Justin Read

We compare the distribution of internal velocity dispersions of galaxy clusters for an observational sample to those obtained from a set of N-body simulations of seven COBE-normalised cosmological scenarios: the standard CDM (SCDM) and a…

Astrophysics · Physics 2009-10-30 S. Borgani , A. Gardini , M. Girardi , S. Gottloeber

What is the role of clusters of galaxies in probing the large-scale velocity field of the universe? We investigate the distribution of peculiar velocities of clusters of galaxies in the popular low-density ($\Omega=0.3$) flat…

Astrophysics · Physics 2009-10-22 Neta A. Bahcall , Renyue Cen , Mirt Gramann

The standard method of measuring the galaxy pairwise velocity dispersion on small scales is heavily weighted by the densest regions in a way that is difficult to calibrate. We propose a new statistic which measures the small-scale velocity…

Astrophysics · Physics 2009-10-30 Michael A. Strauss , Jeremiah P. Ostriker , Renyue Cen

One of the main problems of observational cosmology is to determine the range in which a reliable measurement of galaxy correlations is possible. This corresponds to determine the shape of the correlation function, its possible evolution…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Francesco Sylos Labini , Daniil Tekhanovich , Yurij V. Baryshev

Large redshift surveys of galaxies and clusters are providing the first opportunities to search for distortions in the observed pattern of large-scale structure due to such effects as gravitational redshift. We focus on non-linear scales…

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

The analysis of the vertical velocity dispersion of disc stars is the most direct astronomical means of estimating the local dark matter density, $\rho_{DM}$. Current estimates based on the mid-plane dynamic density use a local baryonic…

Astrophysics of Galaxies · Physics 2015-08-06 Frederic V. Hessman

We study the projection effects on various observables of clusters of galaxies at redshift near zero, including cluster richness, velocity dispersion, X-ray luminosity, three total mass estimates (velocity-based, temperature-based and…

Astrophysics · Physics 2009-10-28 Renyue Cen

Self-consistent N-body simulations are efficient tools to study galactic dynamics. However, using them to study individual trajectories (or ensembles) in detail can be challenging. Such orbital studies are important to shed light on global…

Astrophysics of Galaxies · Physics 2015-06-17 T. Manos , Rubens E. G. Machado

To study the impact of sparsity and galaxy bias on void statistics, we use a single large-volume, high-resolution N-body simulation to compare voids in multiple levels of subsampled dark matter, halo populations, and mock galaxies from a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 P. M. Sutter , Guilhem Lavaux , Nico Hamaus , Benjamin D. Wandelt , David H. Weinberg , Michael S. Warren

The massive exploitation of cosmic voids for precision cosmology in the upcoming dark energy experiments, requires a robust understanding of their internal structure, particularly of their density profile. We show that the void density…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 E. Ricciardelli , V. Quilis , J. Varela

We simulate the assembly of a massive rich cluster and the formation of its constituent galaxies in a flat, low-density universe. Our most accurate model follows the collapse, the star-formation history and the orbital motion of all…

Astrophysics · Physics 2009-09-25 Volker Springel , Simon White , Giuseppe Tormen , Guinevere Kauffmann