相关论文: Beyond Inside-Out Growth: Formation and Evolution …

We present first results concerning the metallicities and stellar populations of galaxies formed in a cosmologically motivated simulation. The calculations include dark matter, gas dynamics, radiation processes, star formation, supernovae…

Galaxy disk formation must incorporate the multiphase nature of the interstellar medium. The resulting two-phase structure is generated and maintained by gravitational instability and supernova energy input, which yield a source of…

We study the detailed structure of galaxies at redshifts z > 2 using cosmological simulations with improved modeling of the interstellar medium and star formation. The simulations follow the formation and dissociation of molecular hydrogen,…

I follow a bar from its formation, via its evolution, to its destruction and, perhaps, regeneration. I discuss the main features at each stage and particularly the role of the halo. Bars can form even in sub-maximum discs. In fact, such…

I review briefly some dynamical models of structures in the outer parts of disc galaxies, including models of polar rings, tidal tails and bridges. I then discuss the density distribution in the outer parts of discs. For this, I compare…

Using numerical hydrodynamics simulations we studied the gravitational collapse of pre-stellar cores of sub-solar mass embedded into a low-density external environment. Four models with different magnitude and direction of rotation of the…

We analyze the formation and evolution of the stellar components in "Eris", a 120 pc-resolution cosmological hydrodynamic simulation of a late-type spiral galaxy. The simulation includes the effects of a uniform UV background, a…

Galaxy disks evolve through angular momentum transfers between sub-components, like gas, stars, or dark matter halos, through non axi-symmetric instabilities. The speed of this evolution is boosted in presence of a large fraction of cold…

We use a series of idealized, numerical SPH simulations to study the formation and evolution of galactic, gas-rich disks forming from gas infall within dark matter halos. The temperature and density structure of the gas is varied in order…

We investigate a model of disk galaxies whereby viscous evolution of the gaseous disk drives material inwards to form a proto-bulge. We start from the standard picture of disk formation through the settling of gas into a dark halo potential…

The spherical gravitational collapse and virialization of arbitrary density fluctuations in an expanding universe is studied. In the context of the standard cosmological model and the peak $ansatz$, disk galaxies are supposed to be the…

In this paper we adopt a chemical evolution model, which is an improved version of the Chiappini, Matteucci and Gratton (1997) model, assuming two main accretion episodes for the formation of the Galaxy. The present model takes into account…

The outer stellar halos of galaxies contain vital information about the formation history of galaxies, since the relaxation timescales in the outskirts are long enough to keep the memory, while the information about individual formation…

Empirical star formation laws from the last 20 years are reviewed with a comparison to simulations. The current form in main galaxy disks has a linear relationship between the star formation rate per unit area and the molecular cloud mass…

We study global star formation thresholds in the outer parts of galaxies by investigating the stability of disk galaxies embedded in dark halos. The disks are self-gravitating, contain metals and dust, and are exposed to UV radiation. We…

Understanding star formation is problematic as it originates in the large scale dynamics of a galaxy but occurs on the small scale of an individual star forming event. This paper presents the first numerical simulations to resolve the star…

We implement a numerical model reported in the literature to simulate the evolution of a galaxy composed of four matter components, such as: a dark-matter halo; a rotating disk of stars; a spherical bulge of stars and a ring of molecular…

We show, using the N-body code GADGET-2, that stellar scattering by massive clumps can produce exponential discs, and the effectiveness of the process depends on the mass of scattering centres, as well as the stability of the galactic disc.…

The radial profiles of stars in disc galaxies are observed to be either purely exponential (Type-I), truncated (Type-II) or anti-truncated (Type-III) exponentials. Controlled formation simulations of isolated galaxies can reproduce all of…

The formation of protostars and their disks has been understood as the result of the gravitational collapse phase of an accumulation of dense gas that determines the mass reservoir of the star-disk system. Against this background, the…