相关论文: Dwarf Spheroidal Satellite Formation in a Reionize…
Dwarf spheroidal (dSph) galaxies present an evolutionary puzzle that we explore in 40 early- and late-type dwarfs in the Local Group and nearby field. Although dSphs formed stars over extended periods, today all but one are free of…
We review numerical work carried out over the last decade on the role of environmental mechanisms in shaping the nature of the faintest galaxies known, dwarf spheroidals (dSphs). In particular we discuss a model in which dSphs originated…
Dwarf spheroidal galaxies are the most dark matter dominated systems in the nearby Universe and their origin is one of the outstanding puzzles of how galaxies form. Dwarf spheroidals are poor in gas and stars, making them unusually faint,…
The aim of this paper is to cast light on the formation and evolution of elliptical galaxies by means of N-body/hydro-dynamical simulations that include star formation, feed-back and chemical evolution. Particular attention is paid to the…
We use numerical simulations to study a formation scenario for dwarf spheroidal galaxies in which their stellar populations are the products of the dissolution of open star clusters and stellar associations within cosmological dark matter…
We present a large sample of fully self-consistent hydrodynamical Nbody/Tree-SPH simulations of isolated dwarf spheroidal galaxies (dSphs). It has enabled us to identify the key physical parameters and mechanisms at the origin of the…
Dwarf spheroidal galaxies are regarded as the basic building blocks in the formation of larger galaxies and are believed to be the most dark matter dominated systems known in the Universe. There are several models that attempt to explain…
We present results of high resolution hydrodynamical simulations of the formation and evolution of dwarf galaxies. Our simulations start from cosmological initial conditions at high redshift. They include metal-dependent cooling, star…
Dwarf spheroidal galaxies that form in halo substructures provide stringent constraints on dark matter annihilation. Many ultrafaint dwarfs discovered with modern surveys contribute significantly to these constraints. At present, because of…
There appears to exist a conflict between the standard structure formation theory and the existence of the faint dwarf spheroidal galaxies in the Local Group. Theoretical considerations suggest that a cold dark matter universe has been a…
The long term time evolution of tidal dwarf satellite galaxies with two different initial densities orbiting a host galaxy that resembles the Milky Way has been studied using a large set of Newtonian N-Body simulations. From the simulations…
We propose a simple model for the formation of dwarf spheroidal galaxies, in which stars are assumed to have formed from isothermal gas in hydrostatic equilibrium inside extended dark matter halos. After expelling the leftover gas, the…
Dwarf spheroidal (dSph) galaxies are considered the basic building blocks of the galaxy formation process in the LCDM (Lambda Cold Dark Matter) hierarchical cosmological model. These galaxies are believed to be the most dark matter (DM)…
We argue that, at least a fraction of the newly discovered population of ultra-faint dwarf spheroidal galaxies in the Local Group constitute the fossil relic of a once ubiquitous population of dwarf galaxies formed before reionization with…
We present the star formation histories (SFHs) of early-type dwarf galaxies, dSphs and dEs, in the local universe within z=0.01. The SFHs of early-type dwarf galaxies are characterized by pre-enriched, metal-poor old stellar populations,…
Self-consistent simulations of the dynamical evolution of low-mass satellite galaxies without dark matter on different orbits interacting with an extended Galactic dark halo are described. The calculations proceed for many orbital periods…
The Local Group offers an excellent laboratory for near-field cosmology by permitting us to use the resolved stellar content of its constituent galaxies as probes of galaxy formation and evolution, which in turn is an important means for…
One of the main challenges facing standard hierarchical structure formation models is that the predicted abundance of galactic subhalos with circular velocities of 10-30 km/s is an order of magnitude higher than the number of satellites…
We compare the properties of dwarf galaxies in the Local Group with the simulated galaxies formed before reionization in a cosmological simulation of unprecedented spatial and mass resolution,including radiative feedback effects. We find…
Dwarf spheroidal galaxies are the most insignificant extragalactic stellar systems in terms of their visibility, but potentially very significant in terms of their role in the formation and evolution of much more luminous galaxies. We…