Related papers: Scaling Rrelation in two situations of extreme mer…
Massive clusters of galaxies are very rare in the observable Universe. Even rarer are mergers of such clusters observed close to pericenter passage. Here, we report on one such case: a massive (~ $10^{15}\,M_\odot$) and hot (kT ~ 10 keV)…
Results from a large sample of hydrodynamical/N-body simulations of galaxy clusters in a LCDM cosmology are used to simulate cluster X-ray observations as expected from Chandra observations. The physical modeling of the gas includes…
Galaxies are believed to be in one-to-one correspondence with simulated dark matter subhalos. We use high-resolution N-body simulations of cosmological volumes to calculate the statistical properties of subhalo (galaxy) major mergers at…
Galaxy clusters trace the highest density peaks in the large-scale structure of the Universe. Their clustering provides a powerful probe that can be exploited in combination with cluster mass measurements to strengthen the cosmological…
Thermodynamic profiles from X-ray and millimetre observations of galaxy clusters are often compared under the simplifying assumptions of smooth, spherically symmetric intracluster medium. These approximations lead to expected discrepancies…
The evolution of the properties of the hot gas that fills the potential well of galaxy clusters is poorly known, since models are unable to give robust predictions and observations lack a sufficient redshift leverage and are affected by…
X-ray images of galaxy clusters often show disturbed structures that are indication of cluster mergers. As a complementary to our previous work on dynamical state of 964 clusters observed by the Chandra, we process the X-ray images for 1308…
We examine the systematics affecting the X-ray mass estimators applied to a set of five simulated galaxy clusters. They have been processed through the X-ray Map Simulator, X-MAS, to provide Chandra-like long exposures that are analyzed to…
Cluster mergers drive shocks into the intracluster medium which heat and compress the thermal gas. X-ray observations of shocks can be used to determine the geometry and kinematics of the merger. Merger shocks should also accelerate…
Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. The basic properties of cluster mergers and their…
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…
Rich and massive clusters of galaxies at intermediate redshift are capable of magnifying and distorting the images of background galaxies. A comparison of different mass estimators among these clusters can provide useful information about…
We used archival ROSAT observations to investigate the X-ray surface brightness profiles of a sample of 26 clusters in the redshift range (0.04-0.06). For 15 of these clusters accurate temperature (kT>3.5 keV) were available from the…
We study the impact of merger events on the strong lensing properties of galaxy clusters. Previous lensing simulations were not able to resolve dynamical time scales of cluster lenses, which arise on time scales which are of order a Gyr. In…
We present a theoretical model which aims at predicting the clustering properties of X-ray clusters in flux-limited surveys for different cosmological scenarios. The model uses the theoretical and empirical relations between mass,…
We selected an unbiased, flux-limited and almost volume-complete sample of 13 distant, X-ray luminous (DXL, $z\sim 0.3$) clusters and one supplementary cluster at $z=0.2578$ from the REFLEX Survey (the REFLEX-DXL sample). We performed a…
Self-gravitating systems such as elliptical galaxies appear to have a constant specific entropy and obey a scaling law relating their potential energy to their mass. These properties can be interpreted as due to the physical processes…
We use cosmological gas dynamic simulations to investigate the accuracy of galaxy cluster mass estimates based on X-ray observations. The experiments follow the formation of clusters in different cosmological models and include the effects…
We study the statistical properties of mergers between central and satellite galaxies in galaxy clusters in the redshift range $0<z<1$, using a sample of dark-matter only cosmological N-body simulations from Le SBARBINE dataset. Using a…
The application to observational data of the generalized scaling relations (gSR) presented in Ettori et al. (2012) is here discussed. We extend further the formalism of the gSR in the self-similar model for X-ray galaxy clusters, showing…