Back to Volume
Paper: The Discovery and Modeling of O-Type-Like Collisional Ring Galaxies
Volume: 477, Galaxy Mergers in an Evolving Universe
Page: 101
Authors: Wu, Y.-T.; Jiang, I.-G.
Abstract: A new type of ring galaxies is discovered from the catalog of collisional ring galaxies in Madore et al. (2009). They are galaxies with axis-symmetric rings but originally classified as P-type collisional ring galaxies due to the existence of nearby companions. We call them O-Type-Like Collisional Ring Galaxies and model their formation through simulations of head-on galactic mergers. After head-on collisions by dwarf galaxies moving along the symmetric axis of disk galaxies, it was found that the simulations with smaller initial relative velocities between two galaxies, or the cases with heavier dwarf galaxies, could produce rings with higher density contrasts. There are more than one generation of rings in one collision and the lifetime of any generation of rings is about one dynamical time. We found that head-on penetrations could explain O-Type-Like Collisional Ring Galaxies well and the simulated rings resembling the observational images of rings are those at the early stage of one of the ring-generations.
Back to Volume