It is inferred from the symmetrical and luminous X-ray emission of fossil groups that they are mature, relaxed galaxy systems. Cosmological simulations and observations focusing on their dark halo and inter-galactic medium properties confirm their early formation. Recent photometric observations suggest that, unlike the majority of non-fossil brightest group galaxies (BGGs), the central early-t...

The cosmological origin of at least an appreciable fraction of classical gamma-ray bursts (GRBs) is now supported by redshift measurements for a half-dozen faint host galaxies. Still, the nature of the central engine (or engines) that provide the burst energy remains unclear. While many models have been proposed, those currently favored are all based upon the formation of and/or rapid accretion...

Recent observations of UV-/optically selected, massive star forming galaxies at z ≈ 2 indicate that the baryonic mass assembly and star formation history is dominated by continuous rapid accretion of gas and internal secular evolution, rather than by major mergers. We use the Millennium Simulation to build new halo merger trees, and extract halo merger fractions and mass accretion rates. We fin...

This thesis explores the occurrence of mergers between community development corporations (CDC's) in the United States in the past five years. The research examines how mergers between CDC's affect their capacity to achieve their mission and serve their constituents. In addition, the author explores the drivers behind CDC mergers, the impacts from those mergers, and the factors that contribute ...

Galaxy interactions are thought to be one of the main triggers of Active Galactic Nuclei (AGN), especially at high luminosities, where the accreted gas mass during the AGN lifetime is substantial. Evidence for a connection between mergers and AGN, however, remains mixed. Possible triggering mechanisms remain particularly poorly understood for luminous AGN, which are thought to require triggerin...

A popular formation scenario for giant elliptical galaxies proposes that they might have formed from binary mergers of disk galaxies. Difficulties with the scenario that emerged from earlier studies included providing the necessary stellar mass and metallicity, maintaining the tight color-magnitude relation and avoiding phase space limits. In this paper we revisit the issue and put constraints ...

Along with the opening up of China economy, cross-border mergers and acquisitions exert a greater effect on China’s industrial security. This paper is chiefly to discuss the influences of cross-border mergers and acquisitions on China automotive industry security. Based on convincible investigations and researches, this paper analyzes China automotive industry’s domestic demand conditions, self...

We search for ongoing major dry-mergers in a well selected sample of local Brightest Cluster Galaxies (BCGs) from the C4 cluster catalogue. 18 out of 515 early-type BCGs with redshift between 0.03 and 0.12 are found to be in major dry-mergers, which are selected as pairs (or triples) with r-band magnitude difference δmr < 1.5 and projected separation rp < 30 kpc, and showing signatures of inter...

Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. The basic properties of cluster mergers and their effects will be discussed. Mergers drive shocks in the intracluster gas, and these shocks heat the intracluster gas, and should also accelerate nonthermal relativi...

We demonstrate that the large scatter in the ultra-violet (UV) colours of intermediatemass early-type galaxies in the local Universe and the inferred low-level recent star formation in these objects can be reproduced by minor mergers in the standard ΛCDM cosmology. Numerical simulations of mergers with mass ratios ≤ 1:4, with reasonable assumptions for the ages, metallicities and dust propertie...