Related papers: A Merger-Driven Scenario for Cosmological Disk Gal…
We use numerical simulations to examine the structure of merger remnants resulting from collisions of gas-rich spiral galaxies. When the gas fraction of the progenitors is small, the remnants structurally and kinematically resemble…
[Abridged] Typical disc galaxies forming in a LambdaCDM cosmology encounter a violent environment, where they often experience mergers with massive satellites. The fact that disc galaxies are ubiquitous in the local Universe suggests that a…
Galaxy mergers are believed to play a key role in transforming star-forming disk galaxies into quenched ellipticals. Most of our theoretical knowledge about such morphological transformations does, however, rely on idealised simulations…
Disk galaxies are common in our universe and this is a source of concern for hierarchical formation models like LCDM. Here we investigate this issue as motivated by raw merger statistics derived for galaxy-size dark matter halos from LCDM…
We discuss the transitions of galaxy morphologies within the CDM paradigm under the assumption of bulge formation in mergers and disk growth via cooling of gas and subsequent star formation. Based on the relative importance of these two…
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…
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…
It is widely accepted that within the framework of LCDM a significant fraction of giant-disk galaxies has recently experienced a violent galactic merger. We present numerical simulations of such major mergers of gas-rich pure disk galaxies,…
Observations indicate that much of the interstellar gas in merging galaxies may settle into extended gaseous disks. Here, I present simulations of disk formation in mergers of gas-rich galaxies. Up to half of the total gas settles into…
Using the deepest and the most complete set of observations of distant galaxies, we investigate how extended disks could have formed. Observations include spatially-resolved kinematics, detailed morphologies and photometry from UV to…
Galaxy interactions and mergers play a significant, but still debated and poorly understood role in the star formation history of galaxies. Numerical and theoretical models cannot yet explain the main properties of merger-induced…
About two-thirds of present-day, large galaxies are spirals such as the Milky Way or Andromeda, but the way their thin rotating disks formed remains uncertain. Observations have revealed that half of their progenitors, six billion years…
We study the formation of disk-dominated galaxies in a LCDM universe. Their existence is considered to be a challenge for the LCDM cosmology, because galaxy mergers isotropize stellar disks and trigger angular momentum transport in gas…
In order to explain disk galaxy formation within the hierarchical structure formation, it seems that gas rich mergers must play an important role. We review here our previous studies which have shown the importance of mergers at high…
Using three fiducial Nbody+SPH simulations, we follow the merging of two disk galaxies with a hot gaseous halo component each, and examine whether the merger remnant can be a spiral galaxy. The stellar progenitor disks are destroyed by…
In our hierarchical structure-formation paradigm, the observed morphological evolution of massive galaxies -- from rotationally-supported discs to dispersion-dominated spheroids -- is largely explained via galaxy merging. However, since…
Mergers between gas--rich disks and less--massive dwarf galaxies are studied using numerical simulation. As the orbit of a satellite decays through dynamical friction, the primary disk develops large-amplitude spirals in response to its…
Using high resolution SPH simulations in a fully cosmological Lambda CDM context we study the formation of a bright disk dominated galaxy that originates from a "wet" major merger at z=0.8. The progenitors of the disk galaxy are themselves…
We present hydrodynamic simulations of a major merger of disk galaxies, and study the ISM dynamics and star formation properties. High spatial and mass resolutions of 12pc and 4x10^4 M_sol allow to resolve cold and turbulent gas clouds…
Disc dominated galaxies can be difficult to accommodate in a hierarchical formation scenario like $\Lambda$CDM, where mergers are an important growth mechanism. However, observational evidence indicates that these galaxies are common. We…