DASH: a library of dynamical subhalo evolution

Abstract

The abundance and demographics of dark matter substructure is important for many areas in astrophysics and cosmological $N$-body simulations have been the primary tool used to investigate them. However, it has recently become clear that the simulations are subject to numerical artefacts, which hampers a proper treatment of the tidal evolution of subhaloes. Unfortunately, no analytical models that accurately describe subhalo evolution exist either. We therefore present a library of idealized, high resolution $N$-body simulations of the tidal evolution of individual subhaloes that can be used to calibrate semi-analytical models and to complement cosmological simulations. The simulations focus on minor mergers, i.e., the mass of the subhalo is much smaller than that of the host halo, such that the impact of dynamical friction is negligible. This setup allows the adoption of a fixed analytical potential for modelling the host halo. The dynamical evolution of subhaloes is followed with $N$-body computations. In the library, four parameters, two of which characterize the subhalo orbit with respect to the host halo, and the two concentrations of the host- and subhalo, are varied over the ranges encountered in cosmological simulations. We show several representative examples from the library that illustrate the evolution of the subhalo mass and velocity dispersion profiles. Additionally, we make publicly available a pre-trained non-parametric model of the subhalo mass evolution based on random forest regression. This model is able to interpolate the simulation data at the 0.1\,dex level and provides efficient access to the data for further use in modelling.

15 pages, 9 figures, 1 table, submitted to MNRAS, the library is available at https://cosmo.oca.eu/dash/

References in corpus (16)

• A universal model for halo concentrations
• Disruption of Dark Matter Substructure: Fact or Fiction?
• Generating Dark Matter Halo Merger Trees
• Dark Matter Substructure in Numerical Simulations: A Tale of Discreteness Noise, Runaway Instabilities, and Artificial Disruption
• Precise constraints on the dark matter content of Milky Way dwarf galaxies for gamma-ray experiments
• SubHaloes going Notts: The SubHalo-Finder Comparison Project
• The Shape of the Gravitational Potential in Cold Dark Matter Halos
• Dark Matter Annihilation in Substructures Revised
• A Statistical Study of Weak Lensing by Triaxial Dark Matter Halos: Consequences for Parameter Estimation
• The Sloan Lens ACS Survey. XII. Extending Strong Lensing to Lower Masses
• Orbital parameters of infalling satellite haloes in the hierarchical $\Lambda$CDM model
• The effect of a disc on the population of cuspy and cored dark matter substructures in Milky Way-like galaxies
• The Dynamics of Subhalos in Warm Dark Matter Models
• Nonlinear evolution of dark matter subhalos and applications to warm dark matter
• The Influence of Mass-Loss from a Star Cluster on its Dynamical Friction -- I. Clusters without Internal Evolution
• Tidal Mass Loss from Collisionless Systems

Cited by in corpus (4)

• The tidal evolution of dark matter substructure -- I. Subhalo density profiles
• Predicting the density profiles of the first halos
• Breaking a dark degeneracy: The gamma-ray signature of early matter domination
• Accelerated orbital decay of supermassive black hole binaries in merging nuclear star clusters