Related papers: The formation of cD galaxies
Central Galaxies (CGs) in massive halos live in unique environments with formation histories closely linked to that of the host halo. In local clusters they have larger sizes ($R_e$) and lower velocity dispersions (sigma) at fixed stellar…
Galaxies in the early universe appear to have grown too big too fast, assembling into massive, monolithic objects more rapidly than anticipated in the hierarchical $\Lambda$CDM structure formation paradigm. The available photometric data…
We study the dominant central giant elliptical galaxies in ``Fossil groups'' using deep optical (R-band) and near infrared (Ks-band) photometry. These galaxies are as luminous as the brightest cluster galaxies (BCGs), raising immediate…
Any realistic theory of galaxy formation must be set in the context of a model for the formation of structure in the universe. We describe a powerful approach -- semi-analytic modelling -- that combines a set of simple rules describing the…
The formation of elliptical galaxies as a result of the merging of spiral galaxies is discussed. We analyse a large set of numerical N-Body merger simulations which show that major mergers can in principle explain the observed isophotal…
Observations of the nearby large galaxies that can be examined in particularly close detail suggest that many have small stellar luminosity fractions in bulges and haloes. Simulations of galaxy formation tend to produce considerably larger…
We test the hypothesis that globular clusters form in supergiant molecular clouds within high-redshift galaxies. Numerical simulations demonstrate that such large, dense, and cold gas clouds assemble naturally in current hierarchical models…
In order to study the mechanism of formation of cD galaxies we search for possible dependencies between the K-band luminosity of cDs and the parameters of their host clusters which we select to have a dominant cD galaxy, corresponding to a…
We use high resolution simulations to study the formation and distribution of galaxies within a cluster which forms hierarchically. We follow both dark matter and baryonic gas which is subject to thermal pressure, shocks and radiative…
Most stars form in dense star clusters deeply embedded in residual gas. These objects must therefore be seen as the fundamental building blocks of galaxies. With this contribution some physical processes that act in the very early and also…
We describe the properties of a sample of galaxy groups with very unusual distributions of galaxy luminosities. The most extreme example has an X-ray luminosity similar to that of the Virgo cluster but has a very low richness, with only one…
In this study, with the aid of N-Body simulations based on quasi-cosmological initial conditions, we have followed the formation and evolution of two models of early-type galaxies, from their separation from global expansion of the Universe…
We present an end-to-end description of the formation process of globular clusters (GCs) which combines a treatment for their formation and dynamical evolution within galaxy haloes with a state-of-the-art semi-analytic simulation of galaxy…
Spiral galaxies have most of their stellar mass in a large rotating disk, and only a modest fraction in a central spheroidal bulge. This poses a major challenge for cosmological models of galaxy formation. Galaxies form at the centre of…
In central regions of non-axisymmetric galaxies high-resolution hydrodynamical simulations indicate spiral shocks, which are capable of transporting gas inwards. The efficiency of transport is lower at smaller radii, therefore instead 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 explore the properties of galaxies on the outskirts of clusters and their dependence on recent dynamical history in order to understand the real impact that the cluster core has on the evolution of galaxies. We analyse the properties of…
We present N-body simulations of galaxy groups embedded in a common halo of matter. We study the influence of the different initial conditions upon the evolution of the group and show that denser configurations evolve faster, as expected.…
(Abridged) Fossil systems are group- or cluster-sized objects whose luminosity is dominated by a very massive central galaxy. In the current cold dark matter scenario, these objects formed hierarchically at an early epoch of the Universe…
We propose that massive central objects form in the centers of the bars which must develop in young high-surface density galactic disks. Large-scale dynamics shuts off the growth of the central mass before it reaches $\sim 2%$ of the disk…