Related papers: Group Scaling Relations From a Cosmological Hydrod…
It has been a long-standing question whether fossil groups are just sampling the tail of the distribution of ordinary groups, or whether they are a physically distinct class of objects, characterized by an unusual and special formation…
The relationship between the X-ray determined temperature $T$ of the intracluster gas and the optical measured velocity dispersion $\sigma$ of the cluster galaxies is often believed to be not only a straightforward but also robust test for…
We revisit the picture of X-ray emission of groups through the study of systematic differences in the optical properties of groups with and without X-ray emission and study the effect of large-scale density field on scaling relations. We…
We consider a sample of 22 nearby clusters of galaxies observed with the Medium Energy Concentrator Spectrometer (MECS) on board of BeppoSAX. They cover the range in gas temperature between 3 and 10 keV, with bolometric X-ray luminosity…
Virialized systems, such as clusters and groups of galaxies, represent an ideal laboratory for investigating the formation and evolution of structure on the largest scales. Furthermore, the properties of the gaseous intracluster medium…
ROSAT observations indicate that approximately half of all nearby groups of galaxies contain spatially extended X-ray emission. The radial extent of the X-ray emission is typically 50-500 kpc or approximately 10-50% of the virial radius of…
The links between the internal structure of galaxy groups and clusters and cosmological parameters are reviewed here. The mass density profiles of clusters, inferred from both optical analyses of the galaxy surface number density profile…
We exmaine the distribution of hot gas in a standard CDM model of the universe using high resolution hydrodynamic simulations. Adopting standard parameters determined from COBE and light element nucleosynthesis, $\sigma_8=1.05$,…
A new, three-dimensional, shock capturing, TVD hydrodynamic code is utilized to determine the distribution of hot gas in a CDM$+\Lambda$ model universe. This open model succeeds in matching local observations of clusters in contrast to the…
Results from hydrodynamical SPH simulations of galaxy clusters are used to investigate the dependence of the final cluster X-ray properties on the numerical resolution and the assumed models for the physical gas processes. Two different…
Theoretical studies of the physical processes in clusters of galaxies are mainly based on the results of numerical simulations, which in turn are often directly compared to X-ray observations. Although trivial in principle, these…
Well-calibrated scaling relations between the observable properties and the total masses of clusters of galaxies are important for understanding the physical processes that give rise to these relations. They are also a critical ingredient…
Galaxy groups and clusters are among the best probes of structure formation and growth in a cosmological context. Most of their baryonic component is dominated by the intracluster medium (ICM), whose thermodynamical properties serve as…
We use a cosmological chemodynamical simulation to study how the group environment impacts the star formation properties of disk galaxies. The simulated group has a total mass of M~8x10^12 Msun and a total X-ray luminosity of L_X~10^41 erg…
As the end products of the hierarchical process of cosmic structure formation, galaxy clusters present some predictable properties, like those mostly driven by gravity, and some others, more affected by astrophysical dissipative processes,…
We study the properties of X-ray galaxy clusters in four cold dark matter models with different baryon fraction $\Omega_{BM}$ ranging from 5 to 20 per cent. By using an original three-dimensional hydrodynamic code based on the piecewise…
We compute the real-space cluster-galaxy cross-correlation xi_cg(r) using the ROSAT-ESO Flux Limited X-ray (REFLEX) cluster survey, a group catalogue constructed from the final version of the 2dFGRS, and galaxies extracted from 2MASS and…
X-ray observations of hot, intergalactic gas in galaxy groups provide a useful means of characterizing the global properties of groups. However, X-ray studies of large group samples have typically involved very shallow X-ray exposures or…
We compare the results of Eulerian hydrodynamic simulations of cluster formation against virial scaling relations between four bulk quantities: the cluster mass, the dark matter velocity dispersion, the gas temperature and the cluster…
The main uncertainty in current determinations of the power spectrum normalization, sigma_8, from abundances of X-ray luminous galaxy clusters arises from the calibration of the mass-temperature relation. We use our weak lensing mass…