Testing the predictions of axisymmetric distribution functions of galactic dark matter with hydrodynamical simulations

Abstract

Signal predictions for galactic dark matter (DM) searches often rely on assumptions on the DM phase-space distribution function (DF) in halos. This applies to both particle (e.g. $p$-wave suppressed or Sommerfeld-enhanced annihilation, scattering off atoms, etc.) and macroscopic DM candidates (e.g. microlensing of primordial black holes). As experiments and observations improve in precision, better assessing theoretical uncertainties becomes pressing in the prospect of deriving reliable constraints on DM candidates or trustworthy hints for detection. Most reliable predictions of DFs in halos are based on solving the steady-state collisionless Boltzmann equation (e.g. Eddington-like inversions, action-angle methods, etc.) consistently with observational constraints. One can do so starting from maximal symmetries and a minimal set of degrees of freedom, and then increasing complexity. Key issues are then whether adding complexity, which is computationally costy, improves predictions, and if so where to stop. Clues can be obtained by making predictions for zoomed-in hydrodynamical cosmological simulations in which one can access the true (coarse-grained) phase-space information. Here, we test an axisymmetric extension of the Eddington inversion to predict the full DM DF from its density profile and the total gravitational potential of the system. This permits to go beyond spherical symmetry, and is a priori well suited for spiral galaxies. We show that axisymmetry does not necessarily improve over spherical symmetry because the (observationally unconstrained) angular momentum of the DM halo is not generically aligned with the baryonic one. Theoretical errors are similar to those of the Eddington inversion though, at the 10-20% level for velocity-dependent predictions related to particle DM searches in spiral galaxies. We extensively describe the approach and comment on the results.

arXiv comment44 pages, 26 figures, 2 tables. Comments are welcome

References in corpus (84)

• A Universal Density Profile from Hierarchical Clustering
• Gaia Data Release 2. Summary of the contents and survey properties
• The Gaia mission
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• Dark Matter Candidates from Particle Physics and Methods of Detection
• The Structure of Dark Matter Haloes in Dwarf Galaxies
• Secluded WIMP Dark Matter
• The mass distribution and gravitational potential of the Milky Way
• A universal angular momentum profile for galactic halos
• The Waning of the WIMP? A Review of Models, Searches, and Constraints
• Non-Baryonic Dark Matter - Observational Evidence and Detection Methods
• Mass models of the Milky Way
• Precise Relic WIMP Abundance and its Impact on Searches for Dark Matter Annihilation
• Analytical Models For Galactic Nuclei
• The Effective Field Theory of Dark Matter Direct Detection
• Non-Perturbative Effect on Dark Matter Annihilation and Gamma Ray Signature from Galactic Center
• Beyond Collisionless Dark Matter: Particle Physics Dynamics for Dark Matter Halo Structure
• A novel determination of the local dark matter density
• Dark Matter Constraints from Observations of 25 Milky Way Satellite Galaxies with the Fermi Large Area Telescope
• Explosive Dark Matter Annihilation
• The Local Dark Matter Density
• Annual Modulation of Dark Matter: A Review
• The Milky Way total mass profile as inferred from Gaia DR2
• Model-independent WIMP Scattering Responses and Event Rates: A Mathematica Package for Experimental Analysis
• Constraining Light Dark Matter with Diffuse X-Ray and Gamma-Ray Observations
• Galactic Searches for Dark Matter
• Gamma Ray Signals from Dark Matter: Concepts, Status and Prospects
• Constraining the Galaxy's dark halo with RAVE stars
• GeV-Scale Thermal WIMPs: Not Even Slightly Dead
• The Sommerfeld enhancement for dark matter with an excited state
• Sommerfeld enhancement: general results from field theory diagrams
• Search for $\gamma$-ray line signals from dark matter annihilations in the inner Galactic halo from ten years of observations with H.E.S.S
• How to Zoom: Bias, Contamination, and Lagrange Volumes in Multimass Cosmological Simulations
• Singlet fermionic dark matter
• Dark Matter Direct Detection Signals inferred from a Cosmological N-body Simulation with Baryons
• The minimal model of fermionic dark matter
• Shape of Dark Matter Haloes in the Illustris Simulation: Effects of Baryons
• Dark Matter Constraints from a Joint Analysis of Dwarf Spheroidal Galaxy Observations with VERITAS
• The fine-grained phase-space structure of Cold Dark Matter halos
• Angular momentum properties of haloes and their baryon content in the Illustris simulation
• A review of action estimation methods for galactic dynamics
• The link between the assembly of the inner dark matter halo and the angular momentum evolution of galaxies in the EAGLE simulation
• Simulated Milky Way analogues: implications for dark matter direct searches
• The Angular Momentum Distribution of Gas and Dark Matter in Galactic Halos
• The local dark matter phase-space density and impact on WIMP direct detection
• A Global Analysis of Dark Matter Signals from 27 Dwarf Spheroidal Galaxies using 11 Years of Fermi-LAT Observations
• Chiral Effective Theory of Dark Matter Direct Detection
• Velocity distributions and annual-modulation signatures of weakly-interacting massive particles
• Astrophysical uncertainties on the local dark matter distribution and direct detection experiments
• The distribution function of dark matter in massive haloes
• A General Analysis of Direct Dark Matter Detection: From Microphysics to Observational Signatures
• Axisymmetric galaxy models wth central BHs, with an application to M32
• Simulated Milky Way analogues: implications for dark matter indirect searches
• Effect of realistic astrophysical inputs on the phase and shape of the WIMP annual modulation signal
• Strong constraints on thermal relic dark matter from Fermi-LAT observations of the Galactic Center
• Cosmic Microwave Background constraint on residual annihilations of relic particles
• Baryonic and dark matter distribution in cosmological simulations of spiral galaxies
• Thermal Relic Abundances of Particles with Velocity-Dependent Interactions
• Anisotropic dark matter distribution functions and impact on WIMP direct detection
• The distribution function of the Galaxy's dark halo
• Anatomy of Eddington-like inversion methods in the context of dark matter searches
• Empirical Determination of Dark Matter Velocities using Metal-Poor Stars
• Lyman-$\alpha$ Constraints on Cosmic Heating from Dark Matter Annihilation and Decay
• The impact of the phase-space density on the indirect detection of dark matter
• Dark Matter Indirect Signatures
• Quark and lepton masses from top loops
• A self-consistent phase-space distribution function for the anisotropic Dark Matter halo of the Milky Way
• Bringing the Galaxy's dark halo to life
• A Search for Dark Matter Annihilation in the Milky Way Halo
• Robust cosmic-ray constraints on $p$-wave annihilating MeV dark matter
• On velocity-dependent dark matter annihilations in dwarf satellites
• The Effective J-Factor of the Galactic Center for Velocity-Dependent Dark Matter Annihilation
• Model-independent constraints on dark matter annihilation in dwarf spheroidal galaxies
• Search for gamma-ray emission from $p$-wave dark matter annihilation in the Galactic Center
• TASI lectures on dark matter models and direct detection
• Search for Gamma-ray Spectral Lines from Dark Matter Annihilation in Dwarf Galaxies with the High-Altitude Water Cherenkov Observatory
• The orbital phase space of contracted dark matter halos
• Cosmological simulations of the same spiral galaxy: the impact of baryonic physics
• Predicting the dark matter velocity distribution in galactic structures: tests against hydrodynamic cosmological simulations
• Gamma-Ray Dark Matter Searches in Milky Way Satellites -- A Comparative Review of Data Analysis Methods and Current Results
• Towards a more rigorous treatment of uncertainties on the velocity distribution of dark matter particles for capture in stars
• Two-integral distribution functions in axisymmetric galaxies: implications for dark matter searches
• Equilibrium axisymmetric halo model for the Milky Way and its implications for direct and indirect DM searches
• Semi-Analytic Models for Dark Matter Halos

Cited by in corpus (1)

• Analytical insight into dark matter subhalo boost factors for Sommerfeld-enhanced $s$- and $p$-wave $\gamma$-ray signals