Coherent Self-Interactions of Dark Matter in the Bullet Cluster

Abstract

Many models of dark matter include self-interactions beyond gravity. A variety of astrophysical observations have previously been used to place limits on the strength of such self-interactions. However, previous works have generally focused either on short-range interactions resulting in individual dark matter particles scattering from one another, or on effectively infinite-range interactions which sum over entire dark matter halos. In this work, we focus on the intermediate regime: forces with range much larger than dark matter particles' inter-particle spacing, but still shorter than the length scales of known halos. We show that gradients in the dark matter density of such halos would still lead to observable effects. We focus primarily on effects in the Bullet Cluster, where finite-range forces would lead either to a modification of the collision velocity of the cluster or to a separation of the dark matter and the galaxies of each cluster after the collision. We also consider constraints from the binding of ultrafaint dwarf galaxy halos, and from gravitational lensing of the Abell 370 cluster. Taken together, these observations allow us to set the strongest constraints on dark matter self-interactions over many orders of magnitude in range below $\sim 10$ kpc, surpassing existing limits by orders of magnitude throughout.

arXiv comment23 pages, 3 figures

References in corpus (36)

• Dark Matter Substructure in Galactic Halos
• Where are the missing galactic satellites?
• A direct empirical proof of the existence of dark matter
• Direct constraints on the dark matter self-interaction cross-section from the merging galaxy cluster 1E0657-56
• Challenges for $\Lambda$CDM: An update
• Observational and Theoretical Constraints on Singular Dark Matter Halos
• The Core-Cusp Problem
• Constraints on the Self-Interaction Cross-Section of Dark Matter from Numerical Simulations of the Merging Galaxy Cluster 1E 0657-5
• Weak lensing mass reconstruction of the interacting cluster 1E0657-558: Direct evidence for the existence of dark matter
• A Textbook Example of a Bow Shock in the Merging Galaxy Cluster 1E0657-56
• The non-gravitational interactions of dark matter in colliding galaxy clusters
• Interacting Dark Matter and Dark Energy
• Light Dark Matter: Models and Constraints
• Strong and weak lensing united III: Measuring the mass distribution of the merging galaxy cluster 1E0657-56
• What does the Bullet Cluster tell us about self-interacting dark matter?
• The speed of the `bullet' in the merging galaxy cluster 1E0657-56
• Baryon bias and structure formation in an accelerating universe
• Chandra Temperature Maps for Galaxy Clusters with Radio Halos
• Tidal Tails Test the Equivalence Principle in the Dark Sector
• 1E0657-56: A Contender for the Hottest Known Cluster of Galaxies
• The Dynamical Status of the Cluster of Galaxies 1E0657-56
• Galilean Equivalence for Galactic Dark Matter
• Effects of asphericity and substructure on the determination of cluster mass with weak gravitational lensing
• An extended halo around an ancient dwarf galaxy
• Dark Matter Cores and Cusps in Spiral Galaxies and their Explanations
• A New Force in the Dark Sector?
• Mass functions in coupled Dark Energy models
• Unveiling dark fifth forces with linear cosmology
• On the cross-section of Dark Matter using substructure infall into galaxy clusters
• Improved constraints from ultra-faint dwarf galaxies on primordial black holes as dark matter
• Galaxy Satellites and the Weak Equivalence Principle
• The Core-Cusp Problem Revisited: ULDM vs. CDM
• Unveiling dark forces with measurements of the Large Scale Structure of the Universe
• Constraints on Dark Matter from Dynamical Heating of Stars in Ultrafaint Dwarfs. Part 1: MACHOs and Primordial Black Holes
• From 100 kpc to 10 Gpc: Dark Matter self-interactions before and after DESI
• Snowmass2021 Cosmic Frontier White Paper: Cosmological Simulations for Dark Matter Physics

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