The Cosmic Evolution of Halo Pairs: I. Global Trends

Abstract

Accumulating evidence suggests that galaxy interactions play an important role in shaping the properties of galaxies. For this reason, cosmological studies focused on the evolution of halo/subhalo pairs are vital. In this paper I describe a large catalogue of halo pairs extracted from the publicly available Millennium Simulation (Springel et. al. 2005). (Throughout this work I use the term `halo' to refer both to individual haloes in the field and subhaloes embedded in larger structures.) Pairs are selected according to whether or not they come within a given critical (comoving) distance dcrit, without the prerequisite that they must merge. Also, a condition requiring haloes to surpass a critical mass Mcrit during their history is imposed. The primary catalogue, consisting of 502,705 pairs, is selected by setting dcrit=1 Mpc/h and Mcrit = 8.6 10^10 Msun/h (equivalent to 100 simulation particles). One of the central goals of this paper is to evaluate the effects of modifying these criteria. For this purpose, additional subcatalogues with more stringent proximity and mass conditions are constructed (i.e., dcrit=200 kpc/h or/and Mcrit=8.6 10^11 Msun/h =1,000 simulation particles). I use a simple five stage picture to perform statistical analyses of their separations, redshifts, masses, mass ratios, and relevant lifetimes. The fraction of pairs that never merge (because one of the members is absorbed by an external halo or both members survive until today) is accounted for. These results provide a broad picture that captures the essential characteristics behind the evolution of halo pairs. This is the first of a series of papers aimed to explore the huge wealth of information encoded in this catalogue. Such investigations will play a fundamental role in future cosmological studies of interacting galaxies and binary (and multiple) quasars.

20 pages, 7 figures, accepted by MNRAS. Replaced to match published version

References in corpus (30)

• The hierarchical formation of the brightest cluster galaxies
• Galaxy Pairs in the Sloan Digital Sky Survey I: Star Formation, AGN Fraction, and the Luminosity/Mass-Metallicity Relation
• Star formation efficiency in galaxy interactions and mergers: a statistical study
• The Nearly Universal Merger Rate of Dark Matter Haloes in Lambda-CDM Cosmology
• Galaxy growth in the concordance $\Lambda$CDM cosmology
• 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
• Star Formation in Close Pairs Selected from the Sloan Digital Sky Survey
• The 2dF-SDSS LRG and QSO survey: Evolution of the Luminosity Function of Luminous Red Galaxies to z=0.6
• AGNs and galaxy interactions
• Merger Rates of Dark-Matter Haloes
• The 2dF-SDSS LRG and QSO survey: evolution of the clustering of luminous red galaxies since z = 0.6
• Growing Massive Black Hole Pairs in Minor Mergers of Disk Galaxies
• Quasar Clustering at $25\kpch$ from a Complete Sample of Binaries
• Luminosity Function Constraints on the Evolution of Massive Red Galaxies Since z~0.9
• Simulating Subhalos at High Redshift: Merger Rates, Counts, and Types
• The growth of luminous red galaxies by merging
• Likely formation of general relativistic radiation pressure supported stars or "eternally collapsing objects"
• The kinetic luminosity function and the jet production efficiency of growing black holes
• Constraints on the merging timescale of luminous red galaxies, or, where do all the halos go?
• PRIMUS: Enhanced Specific Star Formation Rates In Close Galaxy Pairs
• Discovery of a Probable Physical Triple Quasar
• N-body simulation of the Stephan's Quintet
• The stellar evolution of Luminous Red Galaxies, and its dependence on colour, redshift, luminosity and modelling
• Luminous Red Galaxies in hierarchical cosmologies
• Close Pairs as Proxies for Galaxy Cluster Mergers
• Wide-field Infrared Survey Explorer Observations of Young Stellar Objects in the Western Circinus Molecular Cloud
• Detection of Two Carbon-Chain-Rich Cores; CB130-3 and L673-SMM4
• Triplets of Quasars at high redshift I: Photometric data
• Evidence for merging or disruption of red galaxies from the evolution of their clustering

Cited by in corpus (12)

• Mapping galaxy encounters in numerical simulations: The spatial extent of induced star formation
• Interacting galaxies on FIRE-2: The connection between enhanced star formation and interstellar gas content
• Resolving the Discrepancy of Galaxy Merger Fraction Measurements at z ~ 0 - 3
• Spatially resolved star formation and fuelling in galaxy interactions
• Galaxy mergers on a moving mesh: a comparison with smoothed-particle hydrodynamics
• Spatially unassociated galaxies contribute significantly to the blended submillimetre galaxy population: predictions for follow-up observations of ALMA sources
• The Dynamics of Galaxy Pairs in a Cosmological Setting
• Galaxy interactions in IllustrisTNG-100, I: The power and limitations of visual identification
• Living with Neighbors. II. Statistical Analysis of Flybys and Mergers of Dark Matter Halos in Cosmological Simulations
• Star formation in mergers with cosmologically motivated initial conditions
• The ecology of dark matter haloes I: The rates and types of halo interactions
• Rings of star formation: Imprints of a close galaxy encounter