Related papers: Deconstructing A3266: A Major Merger in a Quiet Cl…

The discovery of a striking astrophysical laboratory in the cluster of galaxies Abell 1367 (Sakai et al. 2002) is confirmed with independent imaging and spectroscopic observations and further investigated in the present analysis. Two giant…

Context. Sheen and collaborators recently found that a surprisingly large portion (38%) of massive early-type galaxies in heavy clusters show strong merger-related disturbed features. This contradicts the general understanding that massive…

Preliminary results are presented about a fully self-consistent N-body simulation of a sample of four massive globular clusters in close interaction within the central region of a galaxy. The N-body representation (with N=1.5x10^6 particles…

Here we present the weak lensing results of A1758, which is known to consist of four subclusters undergoing two separate mergers, A1758N and A1758S. Weak lensing results of A1758N agree with previous weak lensing results of clusters…

The hot gas permeating galaxy clusters-the intracluster medium (ICM)-is a key tracer of their assembly history and internal dynamics. Understanding the motion of this gas provides critical insight into processes such as mergers, turbulence,…

We present results of fully self-consistent N-body simulations of the motion of four globular clusters moving in the inner region of their parent galaxy. With regard to previous simplified simulations, we confirm merging and formation of an…

We present results from a spatially resolved spectral analysis of the merging cluster Abell 2256. The long integration time (135 ks) and the good spatial resolution of the MECS onboard BeppoSAX allow us to derive a new and substantially…

We analyse the spatial distribution of halo merger sites using four numerical simulations with high time resolution of structure growth in a Lambda-CDM cosmology. We find no evidence for any large-scale relative bias between mergers and…

We have identified perhaps the largest major galaxy merger ever seen. While analysing Spitzer IRAC images of CL0958+4702, an X-ray selected cluster at z=0.39, we discovered an unusual plume of stars extending $\gtrsim$110 kpc outward from…

The fraction of star-forming galaxies in rich clusters of galaxies increases rapidly with the redshift. This is interpreted as the result of a rapid evolution of cluster galaxies, though its mechanism is not yet clear. One hypothesis is…

Cold fronts were originally interpreted as being the result of subsonic/transonic motions of head-on merging substructures. This merger core remnant model is theoretically justified and hold relatively well for clusters that have clear…

Sub-mm detected galaxies located at redshifts $z > 1$ host a major fraction of the bolometric luminosity at high redshifts due to thermal emission from heated dust grains, yet the nature of these objects remains a mystery. The major problem…

New multi-wavelength (radio, optical & X-rays) observational evidences are presented which show that the nearby (z=0.046), rich cluster of galaxies Abell 3376 is experiencing a major event of binary subcluster merger. The key evidence is…

We report the discovery of the merging cluster, RXCJ2359.3-6042, from the REFLEX II cluster survey and present our results from all three detectors combined in the imaging and spectral analysis of the XMM-Newton data. Also known as Abell…

High-resolution simulations of cosmological structure formation indicate that dark matter substructure in dense environments, like groups and clusters, may survive for a long time. These dark matter subhalos are the likely hosts of…

The environment of the high-z radio galaxy PKS 1138-262 at z~2.2 is a prime example of a forming galaxy cluster. We use deep SINFONI data to perform a detailed study of the kinematics of the galaxies within 60 kpc of the radio core and we…

Simulations of nearby (0.015 < z < 0.025) SDSS galaxies have been used to reproduce as accurately as possible the appearance that they would have on COSMOS ACS images if they had been observed at z ~ 0.7 and z ~ 1.2. By adding the SDSS…

The giant merger remnant galaxy NGC 1316 (Fornax A) is an ideal probe for studying the long-term effects of a past major merger on star cluster systems, given its spectroscopically derived merger age of ~3 Gyr which we reported in a recent…

The newly discovered galaxy cluster 1RXS J0603.3+4214 hosts a 1.9 Mpc long, bright radio relic with a peculiar linear morphology. Using hydrodynamical +N-body AMR simulations of the merger between three initially hydrostatic clusters in an…

We study the incidence and spatial distribution of galaxies that are currently undergoing gravitational merging (M) or that have signs of a post merger (PM) in six galaxy clusters (A754, A2399, A2670, A3558, A3562, and A3716) within the…