Cosmological simulations with rare and frequent dark matter self-interactions

Abstract

Dark matter (DM) with self-interactions is a promising solution for the small-scale problems of the standard cosmological model. Here we perform the first cosmological simulation of frequent DM self-interactions, corresponding to small-angle DM scatterings. The focus of our analysis lies in finding and understanding differences to the traditionally assumed rare DM (large-angle) self scatterings. For this purpose, we compute the distribution of DM densities, the matter power spectrum, the two-point correlation function and the halo and subhalo mass functions. Furthermore, we investigate the density profiles of the DM haloes and their shapes. We find that overall large-angle and small-angle scatterings behave fairly similarly with a few exceptions. In particular, the number of satellites is considerably suppressed for frequent compared to rare self-interactions with the same cross-section. Overall we observe that while differences between the two cases may be difficult to establish using a single measure, the degeneracy may be broken through a combination of multiple ones. For instance, the combination of satellite counts with halo density or shape profiles could allow discriminating between rare and frequent self-interactions. As a by-product of our analysis, we provide - for the first time - upper limits on the cross-section for frequent self-interactions.

13 pages, 16 figures + appendices, accepted for publication in MNRAS

References in corpus (24)

• Array Programming with NumPy
• Constraints on the Self-Interaction Cross-Section of Dark Matter from Numerical Simulations of the Merging Galaxy Cluster 1E 0657-5
• The non-gravitational interactions of dark matter in colliding galaxy clusters
• Cores in Dwarf Galaxies from Dark Matter with a Yukawa Potential
• A mass-dependent density profile for dark matter haloes including the influence of galaxy formation
• Building Merger Trees from Cosmological N-body Simulations
• Dwarf galaxies in CDM and SIDM with baryons: observational probes of the nature of dark matter
• HBT+: an improved code for finding subhalos and building merger trees in cosmological simulations
• Hunting for Galaxies and Halos in simulations with VELOCIraptor
• Self-Scattering for Dark Matter with an Excited State
• The core-cusp problem: a matter of perspective
• Cosmic particle colliders: simulations of self-interacting dark matter with anisotropic scattering
• Strong lensing signatures of self-interacting dark matter in low-mass halos
• Core-collapse, evaporation and tidal effects: the life story of a self-interacting dark matter subhalo
• The central densities of Milky Way-mass galaxies in cold and self-interacting dark matter models
• Dissipative Dark Matter on FIRE: I. Structural and kinematic properties of dwarf galaxies
• A Critical Assessment of Solutions to the Galaxy Diversity Problem
• Degeneracies Between Self-interacting Dark Matter and Supernova Feedback as cusp-core transformation mechanisms
• The Effects of Dark Matter and Baryonic Physics on the Milky Way Subhalo Population in the Presence of the Large Magellanic Cloud
• The Signatures of Self-Interacting Dark Matter and Subhalo Disruption on Cluster Substructure
• Dark Matter in Galaxy Clusters: a Parametric Strong Lensing Approach
• Constraining Self-Interacting Dark Matter with Dwarf Spheroidal Galaxies and High-resolution Cosmological $N$-body Simulations
• The impact of Self-Interacting Dark Matter on the Intrinsic Alignments of Galaxies
• Testing extensions to LCDM on small scales with forthcoming cosmic shear surveys