Related papers: Substructure and Tidal Debris in Local Galaxies: M…
In the CDM cosmological framework structures grow from merging with smaller structures. Merging should have observable effects on galaxies including destroying disks and creating spheroids. This proceeding aims to give a brief overview of…
It has been recently shown that the halo near the Sun contains several kinematic substructures associated to past accretion events. For the more distant halo, there is evidence of large-scale density variations -- in the form of stellar…
The phase-space structure of our Galaxy holds the key to understand and reconstruct its formation. The Lambda-CDM model predicts a richly structured phase-space distribution of dark matter and (halo) stars, consisting of streams of…
Tidal debris from infalling satellites can leave observable structure in the phase-space distribution of the Galactic halo. Such substructure can be manifest in the spatial and/or velocity distributions of the stars in the halo. This paper…
The stellar debris structures that have been discovered around the Milky Way and other galaxies are thought to be formed from the disruption of satellite stellar systems --- dwarf galaxies or globular clusters --- by galactic tidal fields.…
Our Galaxy is thought to have undergone an active evolutionary history dominated by star formation, the accretion of cold gas, and, in particular, mergers up to 10 gigayear ago. The stellar halo reveals rich fossil evidence of these…
We are entering an era in which we will be able to detect and characterize hundreds of dwarf galaxies within the Local Volume. It is already known that a strong dichotomy exists in the gas content and star formation properties of field…
Optical and X-ray studies have established the prevalence of significant substructure in clusters of galaxies, indicating that clusters are young systems, and that recent major mergers have occurred in many clusters. Numerical simulations…
If the Galaxy formed hierarchically through the accretion of smaller satellite galaxies we might hope to find signatures of this in the halo's phase-space distribution. I review theoretical ideas about what form these signatures should…
Aims. Several kinematic and chemical substructures have been recently found amongst Milky Way halo stars with retrograde motions. It is currently unclear how these various structures are related to each other. This Letter aims to shed light…
We search for signatures of recent galaxy close interactions and mergers in a sample of 202 early-type galaxies in the local universe from the public SDSS Stripe82 deep images ($\mu_r \sim 28.5$ mag arcsec$^{-2}$). Using two different…
The hierarchical model of galaxy formation predicts that the Milky Way halo is populated by tidal debris of dwarf galaxies and globular clusters. Due to long dynamical times, debris from the lowest mass objects remains coherent as thin and…
Galaxy haloes contain fundamental clues about the galaxy formation and evolution process: hierarchical cosmological models predict haloes to be ubiquitous, and to be (at least in part) the product of past merger and/or accretion events. The…
We have developed a new semi-analytic model for the formation and evolution of structure on galaxy, group and cluster scales. The model combines merger trees with a detailed, spatially resolved description of the dynamical evolution of halo…
It is now generally believed that galaxies were built up through gravitational amplification of primordial fluctuations and the subsequent merging of smaller precursor structures. The stars of the structures that assembled to form the Milky…
[Abridged] Within the hierarchical framework for galaxy formation, minor merging and tidal interactions are expected to shape all large galaxies to the present day. As a consequence, most seemingly normal disk galaxies should be surrounded…
As galaxies form hierarchically, larger satellites may accrete alongside smaller companions in group infall events. This coordinated accretion is likely to have left signatures in the Milky Way's stellar halo at the present day. Our goal is…
In a hierarchical merging scenario, the outer parts of a galaxy are a fossil record of the galaxy's early history. Observations of the outer disks and halos of galaxies thus provide a tool to study individual galaxy histories and test…
Numerical simulations of dwarf spheroidal galaxies undergoing several close encounters with the Milky Way are described. By comparing our models to observed properties of the recently discovered dwarf galaxy in Sagittarius (Sgr), we discuss…
We use numerical simulations to examine the substructure within galactic and cluster mass halos that form within a hierarchical universe. Clusters are easily reproduced with a steep mass spectrum of thousands of substructure clumps that…