Related papers: Achieving Convergence in Galaxy Formation Models b…
We present a new semi-analytical model of galaxy formation, GECO (Galaxy Evolution COde), aimed at a better understanding of when and how the two processes of star formation and galaxy assembly have taken place. Our model is structured into…
Cosmology requires at least half of the baryons in the Universe to be in the intergalactic medium, much of which is believed to form hot coronae around galaxies. Star-forming galaxies must be accreting from their coronae. HI observations of…
We construct merger trees based on the extended Press-Schechter theory (EPS) in order to study the merger rates of dark matter haloes over a range of present day mass ($10^{10}M_{\sun}\leq M_0 \leq10^{15}M_{\sun}$), progenitor mass…
The current status of numerical simulations of galaxy formation is reviewed. After a short description of the main numerical simulation techniques, three sample applications illustrate how numerical simulations have provided deeper insight…
The distribution of galaxy morphological types is a key test for models of galaxy formation and evolution, providing strong constraints on the relative contribution of different physical processes responsible for the growth of the…
We introduce the contour process to describe the geometrical properties of merger trees. The contour process produces a one-dimensional object, the contour walk, which is a translation of the merger tree. We portray the contour walk through…
The large number of galaxies imaged by digital sky surveys reinforces the need for computational methods for analyzing galaxy morphology. While the morphology of most galaxies can be associated with a stage on the Hubble sequence,…
We use morphological measurements and the scatter of clusters about observed and simulated scaling relations to examine the impact of merging and core-related phenomena on the structure of galaxy clusters. All relations constructed from…
A crucial yet challenging task in galaxy evolution studies is the identification of distant merging galaxies, a task which suffers from a variety of issues ranging from telescope sensitivities and limitations to the inherently chaotic…
We apply updated semi-analytic galaxy formation models simultaneously to the stored halo/subhalo merger trees of the Millennium and Millennium-II simulations. These differ by a factor of 125 in mass resolution, allowing explicit testing of…
Motivated by the closest major merger, the Antennae Galaxies (NGC4038/4039), we want to improve our genetic algorithm based modeling code Minga (Theis 1999). The aim is to reveal the major interaction and galaxy parameters, e.g. orbital…
We take a deep learning-based approach for galaxy merger identification in Subaru HSC-SSP, specifically through the use of deep representation learning and fine-tuning, with the aim of creating a pure and complete merger sample within the…
We study merger histories of dark-matter haloes in a suite of N-body simulations that span different cosmological models. The simulated cases include the up-to-date WMAP5 cosmology and other test cases based on the Einstein-deSitter…
The evolution of dense star clusters is followed by direct high-accuracy N-body simulation. The problem is to first order a gravitational N-body problem, but stars evolve due to astrophysics and the more massive ones form black holes or…
We investigate the environmental dependence of galaxy mergers using high-resolution imaging data from the Hyper Suprime-Cam (HSC) Subaru Strategic Program. We focus on galaxy groups and clusters at $z < 0.2$ identified by the Sloan Digital…
We simulate the growth of large-scale structure in the universe using a N-body code. By combining these simulations with a Monte-Carlo method, we generate galaxy distributions at present that reproduces the observed morphology-density…
We investigate phenomenological models of star formation and supernova feedback in N-body/SPH simulations of galaxy formation. First, we compare different prescriptions in the literature for turning cold gas into stars neglecting feedback…
Merging galaxies play a key role in galaxy evolution, and progress in our understanding of galaxy evolution is slowed by the difficulty of making accurate galaxy merger identifications. We use GADGET-3 hydrodynamical simulations of merging…
Massive star clusters observed in galaxy mergers are often suggested to be progenitors of globular clusters. To study this hypothesis, we performed the highest resolution simulation of a gas-rich galaxy merger so far. The formation of…
We present simulations of the formation and evolution of galaxy clusters in the Cold Dark Matter cosmogony. Clusters with a wide range of mass were selected from previous N-body models, and were resimulated at higher resolution using a…