Galactic disc heating by density granulation in fuzzy dark matter simulations

Abstract

Fuzzy dark matter (FDM), an attractive dark matter candidate comprising ultralight bosons (axions) with a particle mass $m_a\sim 10^{-22}$ eV, is motivated by the small-scale challenges of cold dark matter and features a kpc-size de Broglie wavelength. Quantum wave interference inside an FDM halo gives rise to stochastically fluctuating density granulation; the resulting gravitational perturbations could drive significant disc thickening, providing a natural explanation for galactic thick discs. Here we present the first self-consistent simulations of FDM haloes and stellar discs, exploring $m_a=0.2-1.2\times 10^{-22}$ eV and halo masses $M_{\text{h}}=0.7-2.8\times 10^{11}$ M${}_{\odot }$. Disc thickening is observed in all simulated systems. The disc heating rates are approximately constant in time and increase substantially with decreasing $m_a$, reaching $dh/dt\simeq 0.04$ ($0.4$) kpc Gyr${}^{-1}$ and $d{\sigma }_z^2/dt\simeq 4$ ($150$) km${}^2$s${}^{-2}$Gyr${}^{-1}$ for $m_a=1.2$ ($0.2$) $\times 10^{-22}$ eV and $M_{\text{h}}=7\times 10^{10}{\text{M}}_{\odot }$, where $h$ is the disc scale height and ${\sigma }_z$ is the vertical velocity dispersion. These simulated heating rates agree within a factor of two with the theoretical estimates of Chiang et al., confirming that the rough estimate of Church et al. overpredicts the granulation-driven disc heating rate by two orders of magnitude. However, the simulation-inferred heating rates scale less steeply than the theoretically predicted relation $d{\sigma }_z^2/dt\propto m_a^{-3}$. Finally, we examine the applicability of the Fokker-Planck approximation in FDM granulation modelling and the robustness of the $m_a$ exclusion bound derived from the Galactic disc kinematics.

20 pages, 26 figures; Accepted for publication in MNRAS

References in corpus (79)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Array Programming with NumPy
• The Structure of Cold Dark Matter Halos
• The Gaia mission
• The Star Formation Efficiency in Nearby Galaxies: Measuring Where Gas Forms Stars Effectively
• The Apache Point Observatory Galactic Evolution Experiment (APOGEE)
• Ultralight scalars as cosmological dark matter
• The Galaxy in Context: Structural, Kinematic and Integrated Properties
• A Multi-Code Analysis Toolkit for Astrophysical Simulation Data
• Radial Mixing in Galactic Discs
• Cosmic Structure as the Quantum Interference of a Coherent Dark Wave
• The Radial Velocity Experiment (RAVE): first data release
• Chemical evolution with radial mixing
• Simulations of Galaxy Formation in a Lambda CDM Universe II: The Fine Structure of Simulated Galactic Disks
• Understanding the Core-Halo Relation of Quantum Wave Dark Matter, $\psi$DM, from 3D Simulations
• A dynamically young and perturbed Milky Way disk
• Vertical waves in the solar neighbourhood in Gaia DR2
• The Emergence of the Thick Disk in a CDM Universe
• A New Mechanism for Radial Migration in Galactic Disks: Spiral-Bar Resonance Overlap
• The thick disks of spiral galaxies as relics from gas-rich, turbulent, clumpy disks at high redshift
• A dwarf galaxy remnant in Canis Major: the fossil of an in-plane accretion onto the Milky Way
• Structural Parameters of Thin and Thick Disks in Edge-On Disk Galaxies
• Milky Way Satellite Census. III. Constraints on Dark Matter Properties from Observations of Milky Way Satellite Galaxies
• Strong bound on canonical ultra-light axion dark matter from the Lyman-alpha forest
• Galactoseismology: Discovery of Vertical Waves in the Galactic Disk
• Flattening and truncation of stellar discs in edge-on spiral galaxies
• Axion dark matter, solitons, and the cusp-core problem
• The Genesis of the Milky Way's Thick Disk via Stellar Migration
• Formation and structure of ultralight bosonic dark matter halos
• Dynamical heating across the Milky Way disc using APOGEE and $Gaia$
• The GALAH Survey: Observational Overview and Gaia DR1 companion
• A Structural and Dynamical Study of Late-Type, Edge-On Galaxies: II. Vertical Color Gradients and the Detection of Ubiquitous Thick Disks
• Age dissection of the Milky Way discs: red giants in the Kepler field
• Distribution functions for the Milky Way
• First star-forming structures in fuzzy cosmic filaments
• Thickening of galactic disks through clustered star formation
• Isochrone ages for ~3 million stars with the second Gaia data release
• Relaxation in a Fuzzy Dark Matter Halo
• The origin of the Gaia phase-plane spiral
• Ultra-Light Dark Matter in Ultra-Faint Dwarf Galaxies
• Jeans Analysis for Dwarf Spheroidal Galaxies in Wave Dark Matter
• Warp, Waves, and Wrinkles in the Milky Way
• The echo of the bar buckling: phase-space spirals in Gaia DR2
• Disk heating by more than one spiral density wave
• The Subhalo Mass Function and Ultralight Bosonic Dark Matter
• An iterative method for the construction of N-body galaxy models in collisionless equilibrium
• Rotation curves of high-resolution LSB and SPARC galaxies with fuzzy and multistate (ultra-light boson) scalar field dark matter
• GAMER-2: a GPU-accelerated adaptive mesh refinement code -- accuracy, performance, and scalability
• JWST reveals a population of ultra-red, flattened disk galaxies at 2<z<6 previously missed by HST
• Heating of Milky Way disc Stars by Dark Matter Fluctuations in Cold Dark Matter and Fuzzy Dark Matter Paradigms
• The vertical motion history of disk stars throughout the Galaxy
• Einstein rings modulated by wavelike dark matter from anomalies in gravitationally lensed images
• Fundamental relations for the velocity dispersion of stars in the Milky Way
• Kinetic theory of spatially inhomogeneous stellar systems without collective effects
• The Kinematics of Thick Disks in External Galaxies
• Lick Indices in the Thin and Thick Disks of Edge-On Disk Galaxies
• Self-consistent construction of virialized wave dark matter halos
• Soliton Random Walk and the Cluster-Stripping Problem in Ultralight Dark Matter
• Narrowing the mass range of Fuzzy Dark Matter with Ultra-faint Dwarfs
• A lensed radio jet at milli-arcsecond resolution II: Constraints on fuzzy dark matter from an extended gravitational arc
• Large scale inhomogeneity and local dynamical friction
• A Study of ISM of Dwarf Galaxies Using HI Power Spectrum Analysis
• The Extraordinary `Superthin' Spiral Galaxy UGC7321. II. The Vertical Disk Structure
• Spatially Resolved Stellar Kinematics of the Ultra-Diffuse Galaxy Dragonfly 44: II. Constraints on Fuzzy Dark Matter
• The thick disk in the galaxy NGC 4244 from S4G imaging
• On the Random Motion of Nuclear Objects in a Fuzzy Dark Matter Halo
• Evidence for the concurrent growth of thick discs and central mass concentrations from S${}^4$G imaging
• The origin and fate of the Gaia phase-space snail
• Soliton Oscillations and Revised Constraints from Eridanus II of Fuzzy Dark Matter
• Don't cross the streams: caustics from Fuzzy Dark Matter
• Tracing the Dynamical Mass in Galaxy Disks Using HI Velocity Dispersion and its Implications for the Dark Matter Distribution in Galaxies
• A Comprehensive Perturbative Formalism for Phase-Mixing in Perturbed Disks. I. Phase spirals in an Infinite, Isothermal Slab
• Molecular scale height in spiral galaxies
• Very Thin Disc Galaxies in The SDSS Catalog of Edge-on Galaxies
• Bending instability in galactic discs. Advocacy of the linear theory
• Magnification Bias of Distant Galaxies in the Hubble Frontier Fields: Testing Wave vs. Particle Dark Matter Predictions
• Can ultralight dark matter explain the age-velocity dispersion relation of the Milky Way disc: A revised and improved treatment
• If dark matter is fuzzy, the first stars form in massive pancakes
• On the self-consistent time-dependent linearized response of stellar discs to external perturbations

Cited by in corpus (3)

• Fuzzy dark matter simulations
• Dynamical friction in rotating ultralight dark matter galactic cores
• Investigating the vertical distribution of the disk as a function of radial action: Results from simulations