The time-scales of major mergers from simulations of isolated binary galaxy collisions

Abstract

A six-dimensional parameter space based on high-resolution numerical simulations of isolated binary galaxy collisions has been constructed to investigate the dynamical friction timescales, ${\tau }_{\mathrm{mer}}$, for major mergers. Our experiments follow the gravitational encounters between $\sim 600$ pairs of similarly massive late- and early-type galaxies with orbital parameters compliant to the predictions of the LambdaCDM cosmology. We analyze the performance of different schemes for tracking the secular evolution of mergers, finding that the product of the intergalactic distance and velocity is best suited to identify the time of coalescence. In contrast, a widely used merger time estimator such as the exhaustion of the orbital spin is shown to systematically underpredict ${\tau }_{\mathrm{mer}}$, resulting in relative errors that can reach 60% for nearly radial encounters. Regarding the internal spins of the progenitors, we find that they can lead to total variations in the merger times above 30% in highly circular encounters, whereas only that of the principal halo is capable of modulating the strength of the interaction prevailing throughout a merger. The comparison of our simulated merger times with predictions from different variants of a well-known fitting formula has revealed an only partially satisfactory agreement, which has led us to recalculate the values of the coefficients of these expressions to obtain relations that fit perfectly major mergers. The observed biases between data and predictions, that do not only apply to the present work, are inconsistent with expectations from differences in the degree of idealization of the collisions, their metric, spin-related biases, or the simulation set-up. This hints to a certain lack of accuracy of the dynamical friction modelling, arising perhaps from a still not quite complete identification of the parameters governing orbital decay.

arXiv comment20 pages, 11 figures, 3 tables. Accepted for publication in A&A

References in corpus (49)

• A Universal Density Profile from Hierarchical Clustering
• Profiles of dark haloes: evolution, scatter, and environment
• Statistical Properties of X-ray Clusters: Analytic and Numerical Comparisons
• LCDM-based models for the Milky Way and M31 I: Dynamical Models
• Dynamical Friction and Galaxy Merging Timescales
• The Physics of Galaxy Clustering I: A Model for Subhalo Populations
• Galacticus: A Semi-Analytic Model of Galaxy Formation
• Galaxy Formation Theory
• Properties of spherical galaxies and clusters with an NFW density profile
• A fitting formula for the merger timescale of galaxies in hierarchical clustering
• Orbital Parameters of Merging Dark Matter Halos
• Understanding Dual AGN Activation in the Nearby Universe
• A Very Fast and Momentum-Conserving Tree Code
• Statistics of Physical Properties of Dark Matter Clusters
• An investigation into the prominence of spiral galaxy bulges
• On the Life and Death of Satellite Haloes
• Dynamical friction and the evolution of satellites in virialized halos: the theory of linear response
• Tidal tails in CDM cosmologies
• The Rise and Fall of Satellites in Galaxy Clusters
• Inspiralling Supermassive Black Holes: A New Signpost for Galaxy Mergers
• Observability of Dual Active Galactic Nuclei in Merging Galaxies
• Massive binary black holes in galactic nuclei and their path to coalescence
• Type 2 Active Galactic Nuclei with Double-Peaked [OIII] Lines. II. Single AGNs with Complex Narrow-Line Region Kinematics are More Common than Binary AGNs
• Substructure in Dark Halos: Orbital Eccentricities and Dynamical Friction
• Discovery of Four kpc-Scale Binary AGNs
• Active Galactic Nucleus Pairs from the Sloan Digital Sky Survey. I. The Frequency on ~ 5-100 kpc Scales
• The impact of baryons on the spins and shapes of dark matter haloes
• The importance of major mergers in the build up of stellar mass in brightest cluster galaxies at z=1
• A survey of dual active galactic nuclei in simulations of galaxy mergers: frequency and properties
• Galaxy formation in semi-analytic models and cosmological hydrodynamic zoom simulations
• Dynamical friction of massive objects in galactic centres
• A Semi-Analytic dynamical friction model that reproduces core stalling
• The role of major mergers in shaping galaxies at 2<z<4 in the VUDS and VVDS surveys
• Adaptive Optics Imaging of QSOs with Double-Peaked Narrow Lines: Are they Dual AGNs?
• The low frequency of dual AGNs versus the high merger rate of galaxies: A phenomenological model
• Double quasars: probes of black hole scaling relationships and merger scenarios
• Empirical distributions of galactic $\lambda$ spin parameters from the SDSS
• Simulating the evolution of disc galaxies in a group environment. I. The influence of the global tidal field
• The dependence of tidal stripping efficiency on the satellite and host galaxy morphology
• An Improved Model for the Dynamical Evolution of Dark Matter Subhaloes
• The quiescent Hubble flow, local dark energy tests, and pairwise velocity dispersion in a $\Omega =1$ universe
• Properties of Submillimeter Galaxies in a Semi-analytic Model using the "Count Matching" Approach: Application to the ECDF-S
• Efficient N-body Realisations of axisymmetric Galaxies and Haloes
• The Lives of High Redshift Mergers
• Influence of baryonic physics on the merger time-scale of galaxies in N-body/hydrodynamical simulations
• An improved prescription for merger time-scales from controlled simulations
• GECO: Galaxy Evolution COde - A new semi-analytical model of galaxy formation
• Chandrasekhar's Dynamical Friction and non-extensive statistics
• Fitting functions for a disk-galaxy model with different LCDM-halo profiles

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