Related papers: Clusters Have Edges: The Projected Phase SpaceStru…
We study the use of red sequence selected galaxy spectroscopy for unbiased estimation of galaxy cluster masses. We use the publicly available galaxy catalog produced using the semi-analytic model of De Lucia & Blaizot (2007) on the…
We study the systematic bias introduced when selecting the spectroscopic redshifts of brighter cluster galaxies to estimate the velocity dispersion of galaxy clusters from both simulated and observational galaxy catalogues. We select…
Mass around dark matter halos can be divided into "infalling" material and "collapsed" material that has passed through at least one pericenter. Analytical models and simulations predict a rapid drop in the halo density profile associated…
We search for the presence of substructure, a non-Gaussian, asymmetrical velocity distribution of galaxies, and large peculiar velocities of the main galaxies in galaxy clusters with at least 50 member galaxies, drawn from the SDSS DR8. We…
We present the measurements and modelling of the small-to-intermediate scale (0.1--25 Mpc/h) projected and three-dimensional (3D) redshift-space two-point correlation functions (2PCFs) of local galaxies in the Sloan Digital Sky Survey…
We use simulated galaxy surveys to study: i) how galaxy membership in redMaPPer clusters maps to the underlying halo population, and ii) the accuracy of a mean dynamical cluster mass, $M_\sigma(\lambda)$, derived from stacked pairwise…
We present a statistical study of substructure within a sample of LCDM clusters and galaxies simulated with up to 25 million particles. With thousands of subhalos per object we can accurately measure their spatial clustering and velocity…
We present 118 new optical redshifts for galaxies in 12 clusters in the Horologium-Reticulum supercluster (HRS) of galaxies. For 76 galaxies, the data were obtained with the Dual Beam Spectrograph on the 2.3m telescope of the Australian…
We explore the properties of galaxies on the outskirts of clusters and their dependence on recent dynamical history in order to understand the real impact that the cluster core has on the evolution of galaxies. We analyse the properties of…
The proper motions of stars in the outskirts of globular clusters are used to estimate cluster velocity dispersion profiles as far as possible within their tidal radii. We use individual color-magnitude diagrams to select high probability…
We present a simple model for the shape of the distribution function of galaxy peculiar velocities. We show how both nonlinear and linear theory terms combine to produce a distribution which has an approximately Gaussian core with…
The distribution on the sky of clusters of galaxies shows significant association with relatively nearby, large, active galaxies. The pattern is that of clusters paired equidistant across a central galaxy with the apparent magnitudes and…
Numerous methods for finding clusters at moderate to high redshifts have been proposed in recent years, at wavelengths ranging from radio to X-rays. In this paper we describe a new method for detecting clusters in two-band optical/near-IR…
We identify a sample of 324 red and 273 blue face-on spiral galaxies selected from 115 low-redshift (0.014 < z < 0.18) galaxy clusters imaged with CFHT+MegaCam in u- and r-band, KPNO 0.9-meter 2TKA and MOSAIC 8K camera in B and Rc, and…
Early-type galaxies show a strong size evolution with redshift. This evolution is explained by fast "in-situ" star formation at high-$z$ followed by a late mass assembly mostly driven by minor mergers that deposit stars primarily in the…
We use a sample of galaxies from the Two Micron All Sky Survey (2MASS) Extended Source Catalog to refine a matched filter method of finding galaxy clusters that takes into account each galaxy's position, magnitude, and redshift if…
Optical galaxy cluster identification algorithms such as redMaPPer promise to enable an array of astrophysical and cosmological studies, but suffer from biases whereby galaxies in front of and behind a galaxy cluster are mistakenly…
We present distribution functions and spatial correlations of the shapes of dark matter halos derived from Hubble Volume simulations of a LambdaCDM universe. We measure both position and velocity shapes within spheres encompassing mean…
We analyze the spatial and velocity distributions of confirmed members in five massive clusters of galaxies at intermediate redshift (0.5 < z < 0.9) to investigate the physical processes driving galaxy evolution. Based on spectral…
According to the standard cosmological scenario, superclusters are objects that have just passed the turn around point and are collapsing. The dynamics of very few superclusters have been analysed up to now. In this paper we study the…