相关论文: Formation of Galactic Disks
The importance of angular momentum in regulating the sizes of galactic disks and by this their star formation history is highlighted. Tidal torques and accretion of satellites in principle provide enough angular momentum to form disks with…
The standard picture for the formation of disk galaxies has come to face a number of problems related to angular momentum. Numerical simulations produce disks that are too small, and analytical models predict too much low angular momentum…
Galaxy formation in the current cosmological paradigm is a very complex process in which inflows, outflows, interactions and mergers are common events. These processes can redistribute the angular momentum content of baryons. Recent…
We investigate the evolution of angular momentum in simulations of galaxy formation in a cold dark matter universe. We analyse two model galaxies generated in the N-body/hydrodynamic simulations of Okamoto et al. Starting from identical…
Galactic disk formation requires knowledge about the initial conditions under which disk galaxies form, the boundary conditions that affect their secular evolution and the micro-physical processes that drive the multi-phase interstellar…
The $\Lambda$CDM scenario to form galaxies encounters many problems when confronted with observations, namely the prediction of dark matter cusps in all galaxies, and in particular in dwarf irregulars, dominated by dark matter, or the low…
The formation of disk galaxies is one of the most outstanding problems in modern astrophysics and cosmology. We review the progress made by numerical simulations carried out on large parallel supercomputers. Recent progress stems from a…
We present new models for the formation of disk galaxies that improve upon previous models by following the detailed accretion and cooling of the baryonic mass, and by using realistic distributions of specific angular momentum. Under the…
We investigate the influence of the cooling epoch on the formation of galaxies in a cold dark matter dominated universe. Isolated haloes, with circular speeds typical of spiral galaxies, have been selected from a low resolution numerical…
The formation and evolution of galactic disks are complex phenomena, where gas and star dynamics are coupled through star formation and the related feedback. The physical processes are so numerous and intricate that numerical models focus,…
We compute the specific angular momentum distributions of a sample of low mass disk galaxies observed by Swaters. We compare these distributions to those of dark matter haloes obtained by Bullock et al. from high resolution N-body…
We study the dynamics of galactic disk formation and evolution in 'realistic' LambdaCDM haloes with idealized baryonic initial conditions. We add rotating spheres of hot gas at z=1.3 to two fully cosmological dark-matter-only halo…
Until a decade ago, galaxy formation simulations were unable to simultaneously reproduce the observed angular momentum (AM) of galaxy disks and bulges. Improvements in the interstellar medium and stellar feedback modelling, together with…
Cold Dark Matter with a large cosmological constant (LambdaCDM) appears to fit large scale structure observations well. Of the possible small scale problems, the Central Cusps and Too Many Satellites problems now appear to be at least…
We review the current theory of how galaxies form within the cosmological framework provided by the cold dark matter paradigm for structure formation. Beginning with the pre-galactic evolution of baryonic material we describe the analytical…
New simulations are presented which investigate the formation of smaller groups of galaxies in a CDM like universe. The simulations follow the evolution of dark matter and gas and are performed with an SPH code adapted for the…
The processes are investigated by which gas loses its angular momentum during the protogalactic collapse phase, leading to disk galaxies that are too compact with respect to the observations. High-resolution N-body/SPH simulations in a…
We model in simple terms the angular-momentum problems of galaxy formation in CDM cosmologies, and identify the key elements of a scenario that may solve them. The buildup of angular momentum is modeled via dynamical friction and tidal…
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…
The formation of galactic discs and the efficiency of star formation within them are issues central to our understanding of galaxy formation. We have developed a detailed and versatile model of disc formation which combines the strengths of…