Related papers: Mergers and Galaxy Assembly
Stars are most likely to merge or collide in regions of the highest stellar densities, and our own Galactic Center contains many stars packed into a relatively small volume -- even the ambient stellar number density in the central 50 pc is…
High-resolution simulations of cosmological structure formation indicate that dark matter substructure in dense environments, like groups and clusters, may survive for a long time. These dark matter subhalos are the likely hosts of…
This article concerns the formation and structure of dark matter halos, including (1) their radial density profiles, (2) their abundance, and (3) their merger rates. The last topic may be relevant to the nature of the small, bright,…
We analyse the spatial distribution of halo merger sites using four numerical simulations with high time resolution of structure growth in a Lambda-CDM cosmology. We find no evidence for any large-scale relative bias between mergers and…
Recent observations show a large concentration of galaxies at high redshift. At first sight strong clustering of galaxies at high redshifts seems to be in contradiction with the models of structure formation. In this paper we show that such…
We review our analysis of the clustering properties of ``Lyman-break'' galaxies (LBGs) at redshift z~3, previously discussed in Wechsler et al (1998). We examine the likelihood of spikes found by Steidel et al (1998) in the redshift…
I present a biased review of when the epoch of formation of galaxies (both disks and ellipticals) maybe took place. I base my arguments in simple (mostly) analytic models that have been recently developed to reproduce most of the observed…
We present a study of the incidence of active galactic nucleus (AGN) in a sample of major merging systems at 0.3<z<2.5. Galaxies in this merger sample have projected separations between 3 to 15 kpc and are selected from the CANDELS/3D-HST…
We present a study of tidal debris associated with 126 nearby red galaxies selected from the MUSYC and NDWFS surveys. In the full sample 67 galaxies (53%) show morphological signatures of tidal interactions, consisting of broad fans of…
We consider the hypothesis that the formation of elliptical galaxies includes a phase in which star formation is mostly restricted to massive stars, with the bias towards high mass stars increasing with elliptical galaxy mass. The mass…
We explore the galaxy-galaxy merger rate with the empirical model for galaxy formation, Emerge. On average, we find that between $2$ per cent and $20$ per cent of massive galaxies ($\log_{10}(m_{*}/M_{\odot}) \geq 10.3$) will experience a…
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…
Elliptical and S0 galaxies dominate the galaxy population in nearby rich clusters such as Coma. Studies of the evolution of the colors, M/L ratios, and line indices of early-type galaxies indicate that they have been a highly homogeneous,…
I review the major surveys of high redshift galaxies observed using integral field spectroscopy techniques in the visible and in the infrared. The comparison of various samples has to be done with care since they have different properties…
The most active starbursts are found in galaxies with the highest IR luminosities, with peak star formation rates and efficiencies that are over an order of magnitude higher than in normal disk systems. These systems are almost exclusively…
Formation mechanism of present day population of elliptical galaxies have been revisited in the context of hierarchical cosmological models accompanied by accretion and minor mergers through cross correlation function including spatial…
The star formation history of a galaxy is modulated by a plethora of internal processes and environmental conditions. The details of how these evolve and couple together is not fully understood yet. In this work, we study the effects that…
We outline a scenario of galaxy formation in which the gas in galaxy-forming regions was preheated to high entropy by vigorous energy feedback associated with the formation of stars in old ellipticals and bulges and with AGN activity. Such…
The massive galaxies in the young universe, ten billion years ago, formed stars at surprising intensities. Although this is commonly attributed to violent mergers, the properties of many of these galaxies are incompatible with such events,…
We present a semi-analytical model in which galaxy collisions and strong tidal interactions, both in the field and during the collapse phase of groups and clusters help determine galaxy morphology. From a semi-analytical analysis based on…