Related papers: Forming first-ranked early-type galaxies through h…
We present a suite of 100 cosmologically motivated, controlled N-body simulations designed to advance the understanding of the role of purely gravitational dynamics in the early formation of low-mass galaxy groups (~ 1-5 x 10^13 M_sun). In…
We present multi-wavelength observations of the brightest galaxies in four X-ray luminous groups at z~0.37 that will merge to form a cluster comparable in mass to Coma. Ordered by increasing stellar mass, the four brightest group galaxies…
We present a method of including galaxy formation in dissipationless N-body simulations. Galaxies that form during the evolution are identified at several epochs and replaced by single massive soft particles. This allows one to produce…
We use semi-analytic techniques to study the formation and evolution of brightest cluster galaxies (BCGs). We show the extreme hierarchical nature of these objects and discuss the limits of simple ways to capture their evolution. In a model…
Observational evidence indicates that the role of gas is secondary to that of gravity in the formation of the most luminous spheroids inhabiting the centres of galaxy associations, as originally conjectured in the late 80's/early 90's.…
(Abridged) Fossil systems are galaxy associations dominated by a relatively isolated, bright elliptical galaxy, surrounded by a group of smaller galaxies lacking L* objects. We analyzed the near-infrared photometric and structural…
We use a set of twelve high-resolution N-body/hydrodynamical simulations in the $\Lambda$CDM cosmology to investigate the origin and formation rate of fossil groups (FGs), which are X-ray bright galaxy groups dominated by a large elliptical…
We present cosmological N-body resimulations of the assembly of the Brightest Cluster Galaxies (BCGs) in rich clusters. At $z=2$ we populate dark matter subhalos with self-gravitating stellar systems whose abundance and structure match…
Through the analysis of a set of numerical simulations of major mergers between initially non-rotating, pressure supported progenitor galaxies with a range of central mass concentrations, we have shown that: (1) it is possible to generate…
We present collisionless simulations of dry mergers in groups of three to twenty-five galaxies to test the hypothesis that elliptical galaxies form at the centers of such groups. Mock observations of the central remnants confirm their…
Most clusters and groups of galaxies contain a giant elliptical galaxy in their centres which far outshines and outweighs normal ellipticals. The origin of these brightest cluster galaxies is intimately related to the collapse and formation…
We study the luminosity gap, dm12, between the first and second ranked galaxies in a sample of 59 massive galaxy clusters, using data from the Hale Telescope, HST, Chandra, and Spitzer. We find that the dm12 distribution, p(dm12), is a…
We simulate the assembly of a massive rich cluster and the formation of its constituent galaxies in a flat, low-density universe. Our most accurate model follows the collapse, the star-formation history and the orbital motion of all…
Using a resimulation technique, we perform high-resolution cosmological simulations of dry mergers in a massive galaxy cluster identified in the Millennium Run. Our initial conditions include well resolved compound galaxy models consisting…
For the first time, the combination of semi-analytic modelling of galaxy formation and N-body simulations of cosmic structure formation enables us to model, at the same time, both the photometric and the clustering properties of galaxies.…
We present a series of hundreds of collisionless simulations of galaxy group mergers. These simulations are designed to test whether the properties of elliptical galaxies - including the key fundamental plane scaling relation, morphology…
We present a new set of dissipationless N-body simulations to examine the feasibility of creating bright ellipticals (following the Kormendy relation) by hierarchically merging present-day early-type dwarf galaxies, and to study how the…
We have analysed the growth of Brightest Group Galaxies and Brightest Cluster Galaxies (BGGs/BCGs) over the last 3 billion years using a large sample of 883 galaxies from the Galaxy And Mass Assembly Survey. By comparing the stellar mass of…
We study the formation of galaxies by using $N$-body/hydrodynamics simulations to investigate how baryons collect at the centre of dark matter halos. We treat the dark matter as a collisionless fluid and the baryons as an ideal gas. We…
We discuss early results from the first large N-body/hydrodynamical simulation to resolve the formation of galaxies in a cold dark matter universe. The simulation follows the formation of galaxies by gas cooling within dark halos of mass a…