Related papers: Constraints on the fluctuation amplitude and densi…
We use giga-particle N-body simulations to study galaxy cluster populations in Hubble Volumes of LCDM (Omega_m=0.3, Omega_Lambda=0.7) and tCDM (Omega_m=1) world models. Mapping past light-cones of locations in the computational space, we…
We investigate whether the two cosmological discrepancies on the Hubble constant ($H_0$) and the matter fluctuation parameter ($\sigma_8$) are suggesting and compatible with the existence of an additional one on the matter density. Knowing…
We test an analytic model for the two-point correlations of galaxy clusters in redshift space using the Hubble Volume N-body simulations. The correlation function of clusters shows no enhancement along the line of sight, due to the lack of…
(Abriged) Assuming that the hydrostatic equilibrium holds between the intracluster medium and the gravitational potential, we constrain the NFW profiles in a sample of 44 X-ray luminous galaxy clusters observed with XMM-Newton in the…
For the first time the large-scale clustering and the mean abundance of galaxy clusters are analysed simultaneously to get precise constraints on the normalized cosmic matter density $\Omega_m$ and the linear theory RMS fluctuations in mass…
We use the abundance and weak lensing mass measurements of the SDSS maxBCG cluster catalog to simultaneously constrain cosmology and the richness--mass relation of the clusters. Assuming a flat \LambdaCDM cosmology, we find…
The latest cosmological observables analyses seem to converge to a concordant view of the cosmological model: namely the power law Lambda-CDM. The recent WMAP results comfort this new standard model. Nevertheless, some degeneracy in the CMB…
The parameter $\sigma_8$ is the rms mass fluctuations on a scale of $R_8=8h^{-1}$ Mpc and is used to quantify the amplitude of matter fluctuations at linear scales. However, the dependence of $R_8$ on $h$ complicates direct comparisons of…
The mass function of galaxy clusters is a powerful tool to constrain cosmological parameters, e.g., the mass fluctuation on the scale of 8 h^{-1} Mpc, sigma_8, and the abundance of total matter, Omega_m. We first determine the scaling…
In recent years, the availability of large, complete cluster samples has enabled numerous cosmological parameter inference analyses using cluster number counts. These have provided constraints on the cosmic matter density $\Omega_m$ and the…
A precise determination of the mass function is an important tool to verify cosmological predictions of the $\Lambda$CDM model and to infer more precisely the better model describing the evolution of the Universe. Galaxy clusters have been…
Scaling relations of observed galaxy cluster properties are useful tools for constraining cosmological parameters as well as cluster formation histories. One of the key cosmological parameters, sigma8, is constrained using observed clusters…
We derive constraints on the mass-temperature relation of galaxy clusters from their observed luminosity-temperature relation and X-ray temperature function. Adopting the isothermal gas in hydrostatic equilibrium embedded in the universal…
We investigate the linear amplitude of mass fluctuations in the universe, $\sigma_8$, and the present mass density parameter of the Universe, $\Omega_\mathrm{m}$, from the statistical strong gravitational lensing. We use the two populations…
We use the present observed number density of large X-ray clusters to constrain the amplitude of matter density perturbations induced by cosmic strings on the scale of $8 h^{-1}$Mpc ($\sigma_8$), in both open cosmologies and flat models…
We derive constraints on the matter density \Om and the amplitude of matter clustering \sig8 from measurements of large scale weak lensing (projected separation R=5-30\hmpc) by clusters in the Sloan Digital Sky Survey MaxBCG catalog. The…
Cluster abundance measurements are among the most sensitive probes of the amplitude of matter fluctuations in the universe, which in turn can help constrain other cosmological parameters, like the dark energy equation of state or neutrino…
We revisit the estimate of the mass fluctuation amplitude, sigma_8, from the observational X-ray cluster abundance. In particular, we examine the effect of the systematic difference between the cluster virial mass estimated from the X-ray…
We place constraints on the average density (Omega_m) and clustering amplitude (sigma_8) of matter using a combination of two measurements from the Sloan Digital Sky Survey: the galaxy two-point correlation function, w_p, and the…
A complete catalogue of galaxy cluster models can be used to constrain cosmological parameters like $\sigma_8$, the amplitude of the initial density fluctuation spectrum. We focus here on two strong lensing statistics for clusters of…