Galaxy merging and interactions in numerical simulations and in observations
Abstract
In the process of hierarchical structure formation, galaxy merging and interactions are very common. Under the gravitational effect, satellite galaxies enter the main halo sink to the halo center gradually due to the dynamical friction and merging with the central galaxy eventually. High speed encounters in galaxy clusters inject energy to the perturbed galaxy and modify its morphology therefore. Large scale tidal fields from galaxy clusters strip materials off galaxies in clusters and may even disrupt them. Galaxy merging and interactions play an important role in the galaxy evolution. Not only can they change the morphologies of galaxies and affect their star-forming properties, but they are related to the evolution of active galactic nuclei. With the development of theoretical studies based on numerical simulations and observational studies, we have gained more and more knowledge in this field, especially with respect to the theoretical merging timescale, merging statistics in observations, and the role of merging in the evolution of massive galaxies.
