Related papers: Evidence for new physics from clusters ?
In this review, we describe our current understanding of cluster formation: from the general picture of collapse from initial density fluctuations in an expanding Universe to detailed simulations of cluster formation including the effects…
X-ray cluster measurements interpreted with a universal baryon/gas mass fraction can theoretically serve as a cosmological distance probe. We examine issues of cosmological sensitivity for current (e.g. Chandra X-ray Observatory,…
We present a new Particle-Mesh cosmological N-body code for accurately solving the modified Poisson equation of the Quasi Linear formulation of MOND. We generate initial conditions for the Angus (2009) cosmological model, which is identical…
We introduce a new self-consistent structure finding algorithm that parses large scale cosmological structure into clusters, filaments and voids. This structure finding algorithm probes the cosmological structure at multiple scales and…
Galaxy and galaxy clusters exhibit tight robust physical scaling relations between baryons and system dynamics. One such phenomenon is mass discrepancy with two leading solution spaces occupied by LCDM and MOND. Here, we propose an…
We show that the observed mass-to-light ratio of galaxy clusters increases with cluster temperature as expected from cosmological simulations. Contrary to previous observational suggestions, we find a mild but robust increase of M/L from…
The cluster abundance and its redshift evolution are known to be a powerful tool to constrain the amplitude of mass fluctuations \sigma_8 and the mass density parameter \Omega_m0. We study the impact of the finite decay rate of cold dark…
We investigate galaxy clustering and galaxy-mass correlations in the LCDM cosmological model using a large volume SPH simulation. For the most part, the predicted biases between galaxies and dark matter lead to good agreement with current…
Clusters of galaxies, being the largest collapsed structures in the universe, offer valuable insights into the nature of cosmic evolution. Precise calibration of the mass of clusters can be obtained by extracting their gravitational lensing…
A sample of 197 X-ray emitting clusters of galaxies is considered in the context of Milgrom's modified Newtonian dynamics (MOND). It is shown that the gas mass, extrapolated via an assumed $\beta$ model to a fixed radius of 3 Mpc, is…
Galaxy clusters provide us with important information about the cosmology of our universe. Observations of the X-ray radiation or of the SZ effect allow us to measure the density and temperature of the hot intergalactic medium between the…
The X-ray emission from clusters of galaxies is one of the best observational probe to investigate the distribution of dark matter at intermediate and high redshifts. Since the disposition of the intracluster plasma (ICP) responsible of the…
We use a matched filter algorithm to find and study clusters in both N-body simulations artificially populated with galaxies and the 2MASS survey. In addition to numerous checks of the matched filter algorithm, we present results on the…
The abundance of galaxy clusters as a function of mass is determined using the 2dFGRS Percolation-Inferred Galaxy Group (2PIGG) catalogue. This is used to estimate the amplitude of the matter fluctuation spectrum, parametrised by the linear…
According to the standard cold dark matter (CDM) cosmology, the structure of dark halos including those of galaxy clusters reflects their mass accretion history. Older clusters tend to be more concentrated than younger clusters. Their…
Dark matter (DM) models with a non-zero DM-baryon interaction cross section imply energy transfer between DM and baryons. We present a new method of constraining the DM-baryon interaction cross section and DM particle mass for…
We constrain the physical nature of dark matter using the newly identified massive merging galaxy cluster MACSJ0025.4-1222. As was previously shown by the example of the Bullet Cluster (1E0657-56), such systems are ideal laboratories for…
We derive constraints on cosmological parameters using the power spectrum of galaxy clustering measured from the final two-degree field galaxy redshift survey (2dFGRS) and a compilation of measurements of the temperature power spectrum and…
We present a morphological study of 35 X-ray luminous galaxy clusters at 0.15<z<0.3, selected in a similar manner to the Local Cluster Substructure Survey (LoCuSS), for which deep XMM-Newton observations are available. We characterise the…
It is widely recognized that cold dark matter models predict abundant dark matter substructure in halos of all sizes. Galaxy-galaxy lensing provides a unique opportunity to directly measure the presence and the mass of such substructures in…