Related papers: Galactic Disk Warps
We examine metallicities, ages and orbital properties of halo stars in a Milky-Way like disk galaxy formed in the cosmological hydrodynamical MaGICC simulations. Halo stars were either accreted from satellites or they formed in situ in the…
Galactic disks lie at the heart of many of the most pressing astrophysical puzzles. There are sophisticated kinetic theories that describe some aspects of galaxy disk dynamics, but extracting quantitative predictions from those theories has…
We review the evolution of the interstellar medium in disc galaxies, and show, both analytically and by numerical 3D hydrodynamic simulations, that the disc-halo connection is an essential ingredient in understanding the evolution of star…
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…
To understand galaxies and their evolution, it is necessary to describe how the different scales interact: how the microscopic physics, such as star formation, or the large scale physics, such as galaxy interactions may modify the galaxy…
In both observed and simulated galaxies, disk morphologies become more prevalent at higher masses and lower redshifts. To elucidate the physical origin of this trend, we develop a simple analytical model in which galaxy morphology is…
Neutral hydrogen observations of the nearby, edge-on spiral galaxy NGC 891 reveal the presence of an HI halo extending up to at least 5 kpc from the plane. This halo gas appears to rotate 25 to 100 km/s more slowly than the gas in the…
We present first results from a spectroscopic survey of 2000 F/G stars 0.5--5kpc from the Galactic plane, obtained with the 2dF facility on the AAT. These data show the mean rotation velocity of the thick disk about the Galactic center a…
We use N-body/hydrodynamic simulations to study the evolution of the spin of a Milky Way-like galaxy through interactions. We perform a controlled experiment of co-planner galaxy-galaxy encounters and study the evolution of disk spins of…
We study the formation of disks via the cooling flow of gas within galactic haloes using smoothed particle hydrodynamics simulations. These simulations resolve mass scales of a few thousand solar masses in the gas component for the first…
The near proportionality between HI and dark matter in outer galactic disks prompted us to run N-body simulations of galactic disks in which the observed gas content is supplemented by a dark gas component representing between zero and five…
We generate synthetic HI Galactic plane surveys from spiral galaxy simulations which include stellar feedback processes. Compared to a model without feedback we find an increased scale height of HI emission (in better agreement with…
We study the prospects for the current microlensing searches, which have recently discovered several candidates, to yield useful information about the flattening of the Galaxy dark matter halo. Models of HI warps and N-body simulations of…
We present a statistical analysis of halo emission for a sample of 1047 edge-on disk galaxies imaged in five bands by the Sloan Digital Sky Survey (SDSS). Stacking the homogeneously rescaled images of the galaxies, we can measure surface…
New information on the relations between the Galactic disks, the halo, and satellite galaxies is being obtained from elemental abundances of stars having metallicities in the range -1.5 < [Fe/H] < -0.5. The first results for a sample of 26…
The stellar populations of the stellar halo and of the thick disk of the Milky Way reveal much about the merging history that our Galaxy, a typical large disk galaxy, has experienced. Our current understanding, described here, implies a…
After explaining the motivation for this article, I briefly recapitulate the methods used to determine, somewhat coarsely, the rotation curves of our Milky Way Galaxy and other spiral galaxies, especially in their outer parts, and the…
Warps are common vertical asymmetries that appear in the outer parts of the galactic discs, bending one part upwards and the other downwards. Many mechanisms can trigger warp formation, including tidal interactions. The interactions with…
We estimate halo spins for HI-rich galaxies in the Arecibo Legacy Fast Alfa Survey using a semi-analytic approach, examining the relationship between halo spin and stellar surface density. Our findings reveal an inverse correlation in both…
In order to address the question of whether spiral disturbances in galaxy discs are gravitationally coupled to the halo, we conduct simulations of idealized models of disc galaxies. We compare growth rates of spiral instabilities in…