The merger rate of galaxies in the Illustris simulation: a comparison with observations and semi-empirical models

@article{RodriguezGomez2015TheMR,
  title={The merger rate of galaxies in the Illustris simulation: a comparison with observations and semi-empirical models},
  author={Vicente Rodriguez-Gomez and Shy Genel and Mark Vogelsberger and Debora Sijacki and Annalisa Pillepich and Laura V. Sales and Paul Torrey and Gregory F. Snyder and Dylan Nelson and Volker Springel and Chung-Pei Ma and Lars E. Hernquist},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2015},
  volume={449},
  pages={49-64}
}
We have constructed merger trees for galaxies in the Illustris simulation by directly tracking the baryonic content of subhaloes. These merger trees are used to calculate the galaxy–galaxy merger rate as a function of descendant stellar mass, progenitor stellar mass ratio, and redshift. We demonstrate that the most appropriate definition for the mass ratio of a galaxy–galaxy merger consists in taking both progenitor masses at the time when the secondary progenitor reaches its maximum stellar… 

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References

SHOWING 1-10 OF 73 REFERENCES
Galaxy Merger Statistics and Inferred Bulge-to-Disk Ratios in Cosmological SPH Simulations
We construct merger trees for galaxies identified in a cosmological hydrodynamic simulation and use them to characterize predicted merger rates as a function of redshift, galaxy mass, and merger mass
The zCOSMOS redshift survey : Influence of luminosity, mass and environment on the galaxy merger rate
The contribution of major mergers to galaxy mass assembly along cosmic time is an important ingredient to the galaxy evolution scenario. We aim to measure the evolution of the merger rate for both
Merger rates in hierarchical models of galaxy formation
We present an analytical description of the merging of virialized haloes which is applicable to any hierarchical model in which structure grows via gravitational instability. The formulae are an
Early and Rapid Merging as a Formation Mechanism of Massive Galaxies: Empirical Constraints
We present the results of a series of empirical computations regarding the role of major mergers in forming the stellar masses of modern galaxies based on measured galaxy merger and star formation
Mergers and bulge formation in ΛCDM: Which mergers matter?
We use a suite of semi-empirical models to predict the galaxy–galaxy merger rate and relative contributions to bulge growth as a function of mass (both halo and stellar), redshift, and mass ratio.
RESOLVING THE DISCREPANCY OF GALAXY MERGER FRACTION MEASUREMENTS AT z ∼ 0–3
We measure the merger fraction of massive galaxies using the UltraVISTA/COSMOS catalog, complemented with the deeper, higher resolution 3DHST+CANDELS catalog, presenting the largest mass-complete
THE MAJOR AND MINOR GALAXY MERGER RATES AT z < 1.5
Calculating the galaxy merger rate requires both a census of galaxies identified as merger candidates and a cosmologically averaged “observability” timescale 〈Tobs(z)〉 for identifying galaxy mergers.
Introducing the Illustris Project: the evolution of galaxy populations across cosmic time
We present an overview of galaxy evolution across cosmic time in the Illustris Simulation. Illustris is an N-body/hydrodynamical simulation that evolves 2*1820^3 resolution elements in a (106.5Mpc)^3
Galaxy Mergers and Dark Matter Halo Mergers in LCDM: Mass, Redshift, and Mass-Ratio Dependence
We employ a high-resolution ΛCDM N-body simulation to present merger rate predictions for dark matter (DM) halos and investigate how common merger-related observables for galaxies—such as close pair
Simulating subhaloes at high redshift: merger rates, counts and types
Galaxies are believed to be in one-to-one correspondence with simulated dark matter subhaloes. We use high-resolutionN-body simulations of cosmological volumes to calculate the statistical properties
...
...