Simulating Subhalos at High Redshift: Merger Rates, Counts, and Types
arXiv:0810.2537 · doi:10.1111/j.1365-2966.2009.14424.x
Abstract
Galaxies are believed to be in one-to-one correspondence with simulated dark matter subhalos. We use high-resolution N-body simulations of cosmological volumes to calculate the statistical properties of subhalo (galaxy) major mergers at high redshift (z=0.6-5). We measure the evolution of the galaxy merger rate, finding that it is much shallower than the merger rate of dark matter host halos at z>2.5, but roughly parallels that of halos at z<1.6. We also track the detailed merger histories of individual galaxies and measure the likelihood of multiple mergers per halo or subhalo. We examine satellite merger statistics in detail: 15%-35% of all recently merged galaxies are satellites and satellites are twice as likely as centrals to have had a recent major merger. Finally, we show how the differing evolution of the merger rates of halos and galaxies leads to the evolution of the average satellite occupation per halo, noting that for a fixed halo mass, the satellite halo occupation peaks at z~2.5.
17 pages, 12 figures, accepted in MNRAS, version matches published one
References in corpus (16)
- Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
- Subaru Deep Survey V. A Census of Lyman Break Galaxies at z=4 and 5 in the Subaru Deep Fields: Photometric Properties
- Galaxy Merger Morphologies and Time-Scales from Simulations of Equal-Mass Gas-Rich Disc Mergers
- Virial Scaling of Massive Dark Matter Halos: Why Clusters Prefer a High Normalization Cosmology
- The Redshift Evolution of Wet, Dry, and Mixed Galaxy Mergers from Close Galaxy Pairs in the DEEP2 Galaxy Redshift Survey
- A calibration of the relation between the abundance of close galaxy pairs and the rate of galaxy mergers
- The Population of Dark Matter Subhaloes: Mass Functions and Average Mass Loss Rates
- Dark matter subhalos and the dwarf satellites of the Milky Way
- Ongoing Assembly of Massive Galaxies by Major Merging in Large Groups and Clusters from the SDSS
- The Luminosity Dependence of the Galaxy Merger Rate
- Dissipationless Mergers of Elliptical Galaxies and the Evolution of the Fundamental Plane
- Constraints on the merging timescale of luminous red galaxies, or, where do all the halos go?
- E+A and Companion Galaxies - I : A Catalogue and Statistics
- Why are AGN found in High Mass Galaxies?
- Multi-mass schemes for collisionless N-body simulations
- The effect of gas-dynamics on semi-analytic modeling of cluster galaxies