Related papers: Characterising superclusters with the galaxy clust…
In cold dark matter cosmological models, structures form and grow by merging of smaller units. Numerical simulations have shown that such merging is incomplete; the inner cores of halos survive and orbit as "subhalos" within their hosts.…
Observational investigations of the abundance of massive precursors of local galaxy clusters ("proto-clusters") allow us to test the growth of density perturbations, to constrain cosmological parameters that control it, to test the theory…
Protoclusters represent sites of accelerated galaxy formation and extreme astrophysical activity characteristic of dense environments. Identifying massive protoclusters and mapping their spatial structures are therefore crucial first steps…
In the standard theory of growth of the nonbaryonic dark matter, cosmic structures form hierarchically and self-similarly from smaller clumps. The assembly merger tree goes from the linear perturbations in the early universe to highly non…
The total mass of clusters of galaxies is a key parameter to study massive halos. It relates to numerous gravitational and baryonic processes at play in the framework of large scale structure formation, thus rendering its determination…
In the hierarchical theory of galaxy formation, a galaxy overdensity is a hallmark of a massive cosmic structure. However, it is less well understood how different types of galaxies trace the underlying large-scale structure. Motivated by…
To demonstrate the feasibility of studying the epoch of massive galaxy cluster formation in a more systematic manner using current and future galaxy surveys, we report the discovery of a large sample of proto-cluster candidates in the 1.62…
Mapping galaxies at low Galactic latitudes and determining their clustering status are fundamental steps in defining the large-scale structure in the nearby Universe. The VVV Near-IR Galaxy Catalogue (VVV NIRGC) allows us to explore this…
The characterization of the internal structure of the superclusters of galaxies (walls, filaments and knots where the clusters are located) is paramount for understanding the formation of the Large Scale Structure and for outlining the…
Major progresses have been made this last year towards a better knowledge of the invisible mass. Michel Spiro will talk in details about the micro-lensing experiments and their promising results; the ROSAT satellite has provided extended…
The total mass of a galaxy cluster is one of its most fundamental properties. Together with the redshift, the mass links observation and theory, allowing us to use the cluster population to test models of structure formation and to…
The dark matter in Galactic halos, or some fraction of it, may be in the form of dark clusters which consist of small mass objects. Carr & Lacey (1987) have derived the permissible properties of such systems, and proposed the existence of…
Superclusters are the largest relatively isolated systems in the cosmic web. Using the SDSS BOSS survey we search for the largest superclusters in the redshift range $0.43<z<0.71$. We generate a luminosity-density field smoothed over $8…
We present a weak gravitational lensing analysis of supergroup SG1120$-$1202, consisting of four distinct X-ray-luminous groups, that will merge to form a cluster comparable in mass to Coma at $z=0$. These groups lie within a projected…
(Abridged) We present a study of the structure and dynamics of the Corona Borealis Supercluster (z ~ 0.07) based on the redshifts for 528 galaxies in the supercluster. The galaxy distribution within Corona Borealis is clumpy and appears…
We investigate the dynamical state of superclusters in Lambda cold dark matter ($\Lambda$CDM) cosmological models, where the density parameter $\Omega_0=0.2-0.4$ and $\sigma_8$ (the rms fluctuation on the $8h^{-1}$Mpc scale) is $0.7-0.9$.…
This is the first in a series of papers in which we measure accurate weak-lensing masses for 51 of the most X-ray luminous galaxy clusters known at redshifts 0.15<z<0.7, in order to calibrate X-ray and other mass proxies for cosmological…
The mass function of galaxy clusters is a sensitive tracer of the gravitational evolution of the cosmic large-scale structure and serves as an important census of the fraction of matter bound in large structures. We obtain the mass function…
In recent years, significant progress has been made in building new galaxy clusters samples, at low and high redshifts, from wide-area surveys, particularly exploiting the Sunyaev--Zel'dovich (SZ) effect. A large effort is underway to…
We present the first dynamical study of the optically selected Palomar Distant Cluster Survey (PDCS). We show that eleven out of twelve PDCS clusters we observed are real over-densities of galaxies. Most clusters have velocity dispersions…