Dark Matter Self-interactions and Small Scale Structure
read the original abstract
We review theories of dark matter (DM) beyond the collisionless paradigm, known as self-interacting dark matter (SIDM), and their observable implications for astrophysical structure in the Universe. Self-interactions are motivated, in part, due to the potential to explain long-standing (and more recent) small scale structure observations that are in tension with collisionless cold DM (CDM) predictions. Simple particle physics models for SIDM can provide a universal explanation for these observations across a wide range of mass scales spanning dwarf galaxies, low and high surface brightness spiral galaxies, and clusters of galaxies. At the same time, SIDM leaves intact the success of $\Lambda$CDM cosmology on large scales. This report covers the following topics: (1) small scale structure issues, including the core-cusp problem, the diversity problem for rotation curves, the missing satellites problem, and the too-big-to-fail problem, as well as recent progress in hydrodynamical simulations of galaxy formation; (2) N-body simulations for SIDM, including implications for density profiles, halo shapes, substructure, and the interplay between baryons and self-interactions; (3) semi-analytic Jeans-based methods that provide a complementary approach for connecting particle models with observations; (4) merging systems, such as cluster mergers (e.g., the Bullet Cluster) and minor infalls, along with recent simulation results for mergers; (5) particle physics models, including light mediator models and composite DM models; and (6) complementary probes for SIDM, including indirect and direct detection experiments, particle collider searches, and cosmological observations. We provide a summary and critical look for all current constraints on DM self-interactions and an outline for future directions.
This paper has not been read by Pith yet.
Forward citations
Cited by 55 Pith papers
-
An Acceleration is Worth a Hundred Thousand Phase Space Measurements
One acceleration measurement equals ~10^5 phase-space measurements for local dark matter density estimation, with acceleration outperforming Jeans modeling in both equilibrium and perturbed Milky Way simulations.
-
Dark Matter in Draco and Bo\"otes I: Hints of a Core in an Ultra-Faint Dwarf from Simulation-Based Inference
GraphNPE recovers a significantly lower central density for Boötes I consistent with a core while Draco remains marginally cuspy, and demonstrates that higher-order velocity moments reduce bias in dynamical modeling.
-
Disentangling Dark Gauge Symmetries with Deep Learning on the Lund Jet Plane
A generalized parton shower for arbitrary gauge groups plus a Mamba network on Lund jet planes can distinguish dark gauge symmetries even when non-perturbative hadronization details are unknown.
-
Cooling, conduction, compact objects: Gravothermal evolution of dissipative self-interacting dark matter halos
Dissipation in SIDM halos inverts heat conduction, suppresses isothermal cores, and explains an observed strong lens perturber with smaller cross sections or shorter times than the elastic case.
-
First Constraints on the Ellipticities of Self-Interacting Fermionic Dark Matter Admixed Neutron Stars from Continuous Gravitational-Wave Searches
Using LIGO O3 continuous-wave search data, the authors place the first constraints on ellipticities of self-interacting fermionic dark matter admixed neutron stars and exclude regions of the DM parameter space for mas...
-
Reionization Topology as a Probe of Self-Interacting Dark Matter
Self-interacting dark matter increases the Euler characteristic of the reionization ionization field by 60-70% for cross-sections above 2 cm2/g through changes in ionizing source populations.
-
Dark Matter on a Slide
Dark pions stabilized by U(1) flavor symmetry in an SU(3)/SO(3) dark sector obtain the correct thermal relic density through up-scatterings to heavier mesons and dark eta decays, producing LHC signals from long-lived ...
-
Non-Equilibrium Relativistic Core Collapse of Self-Interacting Dark Matter Halos -- Limits On Seed Black Hole Mass
Non-equilibrium relativistic SIDM halo collapse produces seed black holes of mass ~3e-8 of the halo mass at apparent horizon formation.
-
A Nonlocal Realization of MOND that Interpolates from Cosmology to Gravitationally Bound Systems
A nonlocal gravity model interpolates between MOND in bound systems and dark matter-like effects in cosmology.
-
Probing scalar-neutrino and scalar-dark-matter interactions with PandaX-4T
PandaX-4T reports the first direct spectral search for scalar-mediated neutrino self-interactions in 136Xe double beta decay, setting new upper limits for mediator masses below 2 MeV/c².
-
Strongly Interacting Dark Matter admixed Neutron Stars
Strongly interacting dark matter described by a first-principles G2 gauge-theory equation of state can be mixed into neutron stars while remaining compatible with current observational constraints.
-
Variability in Supermassive Black-Hole Accretion Rates in Fuzzy Dark Matter Cores due to Black-Hole Wandering
Numerical simulations find that black-hole wandering in FDM soliton cores produces intermittent accretion, limiting durable boosts except for ~10^7 solar mass seeds in low-sound-speed gas.
-
Wave-optics imprints of dark matter subhalos on strongly lensed gravitational waves. II. Saddle images and detectability
Subhalos produce percent-level modulations in saddle and minimum images; matched-filter analysis yields >5σ combined detections in 62% of realizations for fiducial sources near caustics, projecting 10-20 substructure ...
-
Projecting the ultimate pulsar timing sensitivity to dark matter substructure in a stochastic gravitational wave background
Monte Carlo and ML surrogate framework projects PTA sensitivity to compact DM substructures and shows SGWB weakens it, with only Shapiro searches retaining sensitivity in optimistic cases.
-
Steep Redshift Evolution of the Ionizing Escape Fraction at $z = 5$--$12$: Empirical Constraints and Comparison with Simulations
Empirical three-parameter fit to f_esc(M_h,z) yields steep redshift evolution with population-averaged escape fraction rising from ~2% at z=5 to ~9% at z=12.
-
Self-gravitating quantum stars with a globally relevant Bohm potential
The equilibrium radius of self-gravitating dark fermion stars is determined by the fermion mass once the total mass is given, with the Bohm potential supplying outward pressure for heavier species and inward tension f...
-
Gauged Flavour for Asymmetric Dark Matter
A gauged SO(3) flavour symmetry broken at multiple scales generates SM fermion masses, redistributes a lepton asymmetry into baryon and dark matter asymmetries via sphalerons, and yields dark matter as bound states of...
-
Search for soft unclustered energy patterns containing muons in the final state in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector
No significant excess observed in search for SUEP signatures with muons; exclusion limits set on mediator cross section times branching fraction down to 0.05 fb at 750 GeV.
-
Neutron Portal and Dark Matter-Baryon Coincidence: from UV Completion to Phenomenology
A UV-complete neutron portal model dynamically solves the dark matter-baryon coincidence via a supercooled dark confinement transition that generates GeV-scale asymmetric DM and links to observed gravitational waves.
-
Breaking the UV Luminosity Function Degeneracy:Self-Interacting Dark Matter Constraints from Reionization Topology
21 cm reionization topology breaks the degeneracy between self-interacting dark matter and astrophysical parameters that limits UV luminosity function constraints, enabling robust SIDM limits of σ/m ≳ 1-2 cm²/g indepe...
-
Probing Collapsed Dark Matter Halos with Fast Radio Bursts
Core-collapsed SIDM halos produce longer FRB image time delays than CDM halos, enabling future surveys to constrain self-interaction cross sections above roughly 18-40 cm²/g depending on collapse timing.
-
Scalar-Mediated Inelastic Dark Matter as a Solution to Small-Scale Structure Anomalies
A scalar-mediated inelastic dark matter model with 100 eV splitting, Z2 symmetry forbidding elastic scattering, and a dimension-5 dipole operator reconciles dwarf galaxy observations with cosmological bounds via reson...
-
Self-Interaction of Super-Resonant Dark Matter
Super-resonant dark matter at O(100) GeV masses amplifies self-scattering and annihilation cross sections via combined resonance and Sommerfeld effects, necessitating coupled Boltzmann equations to match observed reli...
-
Self-Interacting Dark Matter with Mass Segregation: A Unified Explanation of Dwarf Cores and Small-Scale Lenses
Two-component SIDM with velocity-dependent inter- and intra-species interactions produces mass segregation that forms dwarf cores and boosts small-scale strong lensing efficiency by a factor of a few.
-
Size Dependence of the Sommerfeld Enhancement for Puffy Dark Matter
Finite size of puffy dark matter is identified as a fundamental factor affecting Sommerfeld enhancement, characterized via two dimensionless parameters, with nugget-type DM showing resonant behavior akin to point-like...
-
Finite-Core Signatures in LISA-Band Wave-Optics Lensing by Low-Mass Dark Matter Halos
Finite cores in low-mass dark matter halos produce distinct complex residuals in LISA-band wave-optics amplification that cannot be fully mimicked by lower-concentration NFW profiles and peak at rc/rs ≃ 0.25-0.3.
-
SIDM and CDM interpretations of the million-solar-mass lensing perturber JVAS B1938+666-$\mathcal{V}$
SIDM core-collapse simulations produce a dense central core matching the lensing perturber, while CDM requires an IMBH with extreme tidal mass loss whose realism is left open.
-
Lyman-$\alpha$ forest constraints on pure and mixed fuzzy dark matter
Lyman-alpha forest data yield m_FDM > 1.9e-21 eV (95% CL) for pure FDM and f_FDM upper limits of 0.07-0.65 for mixed FDM at log10(m_FDM/eV) = -23 to -21.
-
Scalarization of dark matter stars
Scalarization occurs across most of the parameter space for negative coupling parameter β_d in self-interacting dark matter stars, over a broader range than in conventional neutron stars.
-
Dwarf Galaxy Constraints on Interacting Fermionic Dark Matter
MCMC fits of degenerate fermionic dark matter models to eight classical dwarf spheroidal galaxies constrain fermion masses to 100-300 eV and show current data do not strongly favor interacting over non-interacting equ...
-
Gauged Flavour for Asymmetric Dark Matter
A gauged SO(3) flavour symmetry spontaneously broken at multiple scales links SM flavour hierarchies to asymmetric dark matter via leptogenesis and sphaleron redistribution, with DM as bound states of a confining SU(3).
-
Bayesian analysis of density profile of light dark matter elucidating the properties of dark matter admixed neutron stars in the presence of hyperons
Bayesian analysis finds that the likely ranges of light dark-matter fermion mass and exponential density-profile parameter in hyperon-containing neutron stars are nearly independent of the hadronic model for symmetry-...
-
Self-interacting dark matter and core formation in field low-surface-brightness galaxies
Order-of-magnitude estimates exclude a self-interaction cross section of 1 cm²/g for dark matter in isolated low-surface-brightness galaxies while favoring 0.1 cm²/g.
-
Cosmology of Inelastic Self-Interacting Dark Matter: Linear Evolution and Observational Constraints
Inelastic self-interacting dark matter with small mass splitting produces a cutoff in the matter power spectrum at k > 1 h Mpc^{-1} whose location depends on cross-section normalization, velocity dependence, dark matt...
-
Axion-Like Electrophilic Portal for Pion Dark Matter
A minimal electrophilic ALP portal for SIMP pion dark matter widens the allowed parameter space, making an ALP mass of order 10 MeV viable and consistent with the X17 anomaly.
-
Dark QCD Origin of the NANOGrav Signal and Self-Interacting Dark Matter
A dark QCD model with a first-order phase transition at 5-6 MeV produces the NANOGrav SGWB amplitude while supplying self-interacting dark matter via a 40 GeV baryon and 20-50 MeV dilaton, linked by entropy dilution.
-
Nearly Degenerate Majorana Dark Matter and Its Self-Interactions in a Gauged $U(1)_{L_\mu - L_\tau}$ Model
A gauged U(1)_{Lμ-Lτ} model generates nearly degenerate Majorana dark matter whose self-interactions via a light scalar mediator set the relic density, resolve core-cusp anomalies, and fit LZ direct detection plus muo...
-
Bulk viscosity from neutron decays to dark baryons in neutron star matter
Neutron dark decays modify the equation of state and either mildly suppress or strongly enhance bulk viscosity in neutron star merger conditions, depending on the in-medium decay rate.
-
Imprints of energy injection by compact dark stars in the 21-cm signal
Compact dark stars from asymmetric dark matter may inject energy that significantly deviates the 21-cm brightness temperature evolution from standard cosmology, offering a new probe for particle dark matter.
-
Low-Energy Nuclear Recoil Calibration of XENONnT with a $^{88}$YBe Photoneutron Source
XENONnT extracted nuclear recoil light and charge yields in liquid xenon from 0.3 to 5 keV_NR using 474 events from a ⁸⁸YBe source after subtracting 55 background events.
-
Dark Matter Energy Deposition and Production from the Table-Top to the Cosmos
The thesis presents a new 3-to-2 freezeout mechanism, bound-state effects on searches, a new axion interferometric search, reionization assessments, 21-cm constraints, and the DarkHistory code for ionization and therm...
-
Constraining light fermionic dark matter with binary pulsars
Dynamical friction from a degenerate fermionic dark matter background induces measurable secular decay in binary pulsar orbital periods, with sensitivity to fermion masses ≳50 eV and example upper bounds around 1 keV ...
-
Spherically Symmetric Fluid Simulations of Black Hole Accretion in Self-Interacting Dark Matter Halos
1D hydrodynamic simulations find that SIDM heat transport competes with gravity to regulate black hole accretion, enabling rapid growth in SIS profiles up to 10,000 solar masses from a 100 solar mass seed in 2 Myr.
-
Classical and Loop Quantum Cosmology of Interacting Dark Energy: A Dynamical System Analysis with Superfluid Dark Matter and Dust Matter
Dynamical systems analysis shows loop quantum cosmology removes stable attractors in interacting dark energy-dark matter models that exist under classical gravity.
-
Evolution of Compact Stellar Systems in Ultralight Dark Matter Halos: Dependence on Stellar and Dark Matter Parameters
Simulations find metal-richer compact stellar systems resist disruption better in ULDM halos, with tidal fields altering stability and heating strengthening at higher particle masses when system size is much smaller t...
-
Gravothermal Collapse: Robust Against Baryonic Feedback
Baryonic feedback mildly delays but does not stall gravothermal collapse in high-concentration SIDM halos and allows resumption in median-concentration cases, yielding feedback-history-dependent central densities.
-
From Large Telescopes to the MUltiplexed Survey Telescope (MUST)
MUST is a new 6.5 m telescope designed to deliver simultaneous optical spectra for over 20,000 targets across a 5 deg² field, enabling the largest 3D spectroscopic map of the Universe with redshifts for more than 100 ...
-
Constraints on Ultralight Scalar and Dark Photon Dark Matter from PPTA-DR3 and EPTA-DR2
Bayesian analysis of PPTA-DR3 and EPTA-DR2 finds no statistically significant ULDM signals and sets 95% CL upper limits on scalar and dark photon dark matter, improving prior bounds in most mass ranges.
-
Gravitational waves of extreme-mass-ratio inspirals in a rotating black hole with Dehnen dark matter halo
EMRI waveforms in a rotating black hole with Dehnen DM halo show amplitude and phase shifts from Kerr, with mismatch rising as DM mass parameter and black hole spin increase.
-
Constraining dark matter self-interaction from kinetic heating in neutron stars
Observation of neutron stars at 1000-1200 K could constrain asymmetric dark matter self-interaction cross-sections by two orders of magnitude beyond bullet cluster limits.
-
QCD-driven dark matter: AQNs formation and observational tests
Dark matter is composed of composite quark-antiquark objects stabilized by axion domain walls, offering a unified account of dark matter and baryon asymmetry.
-
Constraints on a Light Leptophilic Scalar from Dark-Sector Couplings
A parameter space analysis of a leptophilic scalar mediator model for Majorana dark matter yields a viable sub-GeV region after applying relic density, cosmological, astrophysical, and laboratory constraints.
-
Addressing Standard Model Tensions via X17 Vector Boson
A new X17 vector boson is suggested to alleviate Standard Model tensions while connecting to the dark sector.
-
Self-Interacting Dark Matter in Brown Dwarfs
Brown dwarfs modeled with a self-interacting dark matter fluid component show modified radii and second-order Love numbers due to core accumulation.
-
Dark Energy in the DESI Era: A Brief Review of Evidence, Beyond-$\Lambda$CDM Interpretations, and Tensions
Review of DESI evidence for dynamical dark energy, its dependence on parametrization and datasets, and alternative beyond-LambdaCDM interpretations that may address cosmological tensions.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.