Tidal Stripping and Post-Merger Relaxation of Dark Matter Halos: Causes and Consequences of Mass Loss

Abstract

We study the properties of distinct dark matter halos (i.e., those that are not subhalos) that have a final virial mass $M_{\mathrm{vir}}$ at $z=0$ less than their peak mass ($M_{\mathrm{peak}}$) in the Bolshoi-Planck cosmological simulation. We identify two primary causes of halo mass loss: relaxation after a major merger and tidal stripping by a massive neighbouring halo. Major mergers initially boost $M_{\mathrm{vir}}$ and typically cause the final halo to become more prolate and less relaxed and to have higher spin and lower NFW concentration. As the halo relaxes, high energy material from the recent merger gradually escapes beyond the virial radius, temporarily resulting in a net negative accretion rate that reduces the halo mass by $5-15\%$ on average. Halos that experience a major merger around $z=0.4$ typically reach a minimum mass near $z=0$. Tidal stripping mainly occurs in dense regions, and it causes halos to become less prolate and have lower spins and higher NFW concentrations. Tidally stripped halos often lose a large fraction of their peak mass ($>20\%$) and most never recover (or even reattain a positive accretion rate). Low mass halos can be strongly affected by both post-merger mass loss and tidal stripping, while high mass halos are predominantly influenced by post-merger mass loss and show few signs of significant tidal stripping.

References in corpus (31)

• Planck 2015 results. XIII. Cosmological parameters
• The Structure of Cold Dark Matter Halos
• Planck 2013 results. XVI. Cosmological parameters
• Statistical Properties of X-ray Clusters: Analytic and Numerical Comparisons
• The Rockstar Phase-Space Temporal Halo Finder and the Velocity Offsets of Cluster Cores
• Concentrations of Dark Halos from their Assembly Histories
• MultiDark simulations: the story of dark matter halo concentrations and density profiles
• A universal angular momentum profile for galactic halos
• Gravitationally Consistent Halo Catalogs and Merger Trees for Precision Cosmology
• Properties of Dark Matter Haloes in Clusters, Filaments, Sheets and Voids
• The spin and shape of dark matter haloes in the Millennium simulation of a LambdaCDM universe
• Dark matter and cosmic structure
• The splashback radius as a physical halo boundary and the growth of halo mass
• Toy Models for Galaxy Formation versus Simulations
• The Evolution of Dark Matter Halo Properties in Clusters, Filaments, Sheets and Voids
• The Galaxy-Halo Connection Over The Last 13.3 Gyrs
• Halo and Subhalo Demographics with Planck Cosmological Parameters: Bolshoi-Planck and MultiDark-Planck Simulations
• The Mass Profile and Accretion History of Cold Dark Matter Halos
• Tidal Effects and the Environment Dependence of Halo Assembly
• The Relationship between Galaxy and Dark Matter Halo Size from z~3 to the present
• Mergers and Mass Accretion for Infalling Halos Both End Well Outside Cluster Virial Radii
• Halo assembly bias and the tidal anisotropy of the local halo environment
• Internal properties and environments of dark matter halos
• The Dynamical State and Mass-Concentration Relation of Galaxy Clusters
• Major Mergers Going Notts: Challenges for Modern Halo Finders
• Do Mergers Spin up Dark Matter Halos?
• Dissecting the Evolution of Dark Matter Subhaloes in the Bolshoi Simulation
• On the Physical Origin of Galactic Conformity
• Properties of Dark Matter Halos as a Function of Local Environment Density
• What Do Dark Matter Properties Tell Us About Their Mass Assembly Histories?
• Unbound Particles in Dark Matter Halos

Cited by in corpus (12)

• NIHAO XV: The environmental impact of the host galaxy on galactic satellite and field dwarf galaxies
• Is the dark-matter halo spin a predictor of galaxy spin and size?
• Concentrations of Dark Haloes Emerge from Their Merger Histories
• Evidence for galaxy assembly bias in BOSS CMASS redshift-space galaxy correlation function
• Reignition of Star Formation in Dwarf Galaxies
• The physical origins of low-mass spin bias
• Scaling relations for globular cluster systems in early-type galaxies. II. Is there an environmental dependence?
• A random-walk model for dark matter halo spins
• Implications of Increased Central Mass Surface Densities for the Quenching of Low-mass Galaxies
• The history and mass content of cluster galaxies in the EAGLE simulation
• The galactic acceleration scale is imprinted on globular cluster systems of early-type galaxies of most masses and on red and blue globular cluster subpopulations
• A Multiwavelength Portrait of the 3C 220.3 Lensed System