Impact of baryons on the population of Galactic subhalos and implications for dark matter searches

Abstract

We have used Auriga --a set of state-of-the-art cosmological hydrodynamical simulations of Milky Way-size systems-- to study the impact of baryons on the Galactic subhalo population. A DM-only run counterpart of Auriga allows us to compare results with and without baryons. We repopulate the original suites with low-mass subhalos orders of magnitude lighter than the mass resolution limit, starting from a detailed characterization of Auriga data in the well-resolved subhalo mass range. The survival of low-mass subhalos to tidal forces is unclear and under debate nowadays, thus in our study we stay agnostic and consider two different levels of subhalo resilience to tidal stripping ('fragile' and 'resilient' subhalos). We find baryons to alter the Galactic substructure significantly, by decreasing its overall abundance by a factor $\sim 2.4$ (fragile) and $\sim 1.9$ (resilient) and subhalo concentration --here defined in terms of maximum circular velocity-- by $\sim 1.5$ with respect to the DM-only scenario. This has important consequences for indirect searches of DM. As an example, we investigated the case of using unidentified gamma-ray sources to set constraints on the DM particle properties, assuming some of them may be dark satellites. Our results show the importance of including baryons to properly characterize the Galactic subhalo population, as well as to propose the most optimal subhalo search strategies, not only via its potential DM annihilation products but also through their gravitational signatures (e.g.~stellar streams, strong lensing).

arXiv comment25 pages, 18 figures

References in corpus (88)

• Array Programming with NumPy
• Astropy: A Community Python Package for Astronomy
• A Universal Density Profile from Hierarchical Clustering
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• Particle Dark Matter: Evidence, Candidates and Constraints
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• Supersymmetric Dark Matter
• The Large Area Telescope on the Fermi Gamma-ray Space Telescope Mission
• Large scale bias and the peak background split
• Profiles of dark haloes: evolution, scatter, and environment
• The Aquarius Project: the subhalos of galactic halos
• A History of Dark Matter
• Searching for Dark Matter Annihilation from Milky Way Dwarf Spheroidal Galaxies with Six Years of Fermi-LAT Data
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: I. Morphology of the Sagittarius Core and Tidal Arms
• Clumps and streams in the local dark matter distribution
• Concentration, Spin and Shape of Dark Matter Haloes as a Function of the Cosmological Model: WMAP1, WMAP3 and WMAP5 results
• LCDM-based models for the Milky Way and M31 I: Dynamical Models
• Halo concentrations in the standard LCDM cosmology
• Formation and evolution of galaxy dark matter halos and their substructure
• Observability of Gamma Rays from Dark Matter Neutralino Annihilations in the Milky Way Halo
• WIMP dark matter candidates and searches - current status and future prospects
• Evolution of structure in cold dark matter universes
• A New Era in the Quest for Dark Matter
• The Structural Evolution of Substructure
• Dark matter and cosmic structure
• The Status of the H.E.S.S. Project
• VERITAS: the Very Energetic Radiation Imaging Telescope Array System
• Not so lumpy after all: modeling the depletion of dark matter subhalos by Milky Way-like galaxies
• Disruption of Dark Matter Substructure: Fact or Fiction?
• Detection of a Dark Substructure through Gravitational Imaging
• Dark Matter Substructure in Numerical Simulations: A Tale of Discreteness Noise, Runaway Instabilities, and Artificial Disruption
• The Uchuu Simulations: Data Release 1 and Dark Matter Halo Concentrations
• Particle Models and the Small-Scale Structure of Dark Matter
• Full One-loop Calculation of Neutralino Annihilation into Two Photons
• Survival of Substructure within Dark Matter Haloes
• The flattening of the concentration-mass relation towards low halo masses and its implications for the annihilation signal boost
• The APOSTLE project: Local Group kinematic mass constraints and simulation candidate selection
• Bent by baryons: the low mass galaxy-halo relation
• The Mass Profile and Accretion History of Cold Dark Matter Halos
• A "Baedecker" for the Dark Matter Annihilation Signal
• Milky Way Satellite Census. II. Galaxy--Halo Connection Constraints Including the Impact of the Large Magellanic Cloud
• The Phoenix Project: the Dark Side of Rich Galaxy Clusters
• The Spur and the Gap in GD-1: Dynamical evidence for a dark substructure in the Milky Way halo
• Dark matter local density determination: recent observations and future prospects
• An excess of small-scale gravitational lenses observed in galaxy clusters
• The upper bound on the lowest mass halo
• The Global Dynamical Atlas of the Milky Way mergers: Constraints from Gaia EDR3 based orbits of globular clusters, stellar streams and satellite galaxies
• The chosen few: the low mass halos that host faint galaxies
• Search for Dark Matter Satellites using the FERMI-LAT
• Dark Matter Sub-Halo Counts via Star Stream Crossings
• Detection of substructure with adaptive optics integral field spectroscopy of the gravitational lens B1422+231
• A unified model for the spatial and mass distribution of subhaloes
• Phat ELVIS: The inevitable effect of the Milky Way's disk on its dark matter subhaloes
• On the sensitivity of the HAWC observatory to gamma-ray bursts
• Forensics of Subhalo-Stream Encounters: The Three Phases of Gap Growth
• Properties of Dark Subhaloes from Gaps in Tidal Streams
• The Copernicus Complexio: a high-resolution view of the small-scale Universe
• Can tides disrupt cold dark matter subhaloes?
• Measuring the power spectrum of dark matter substructure using strong gravitational lensing
• The asymptotic tidal remnants of cold dark matter subhalos
• Determining the full satellite population of a Milky Way-mass halo in a highly resolved cosmological hydrodynamic simulation
• Fermi's Sibyl: Mining the gamma-ray sky for dark matter subhaloes
• The tidal evolution of dark matter substructure -- I. Subhalo density profiles
• Dark Matter Subhalos In the Fermi First Source Catalog
• Subhalo destruction in the Apostle and Auriga simulations
• Unidentified sources in the Fermi-LAT second source catalog: the case for DM subhalos
• Aurigaia: mock Gaia DR2 stellar catalogues from the Auriga cosmological simulations
• Precise dark matter relic abundance in decoupled sectors
• LCDM halo substructure properties revealed with high resolution and large volume cosmological simulations
• Is The Gamma-Ray Source 3FGL J2212.5+0703 A Dark Matter Subhalo?
• Unidentified Gamma-ray Sources as Targets for Indirect Dark Matter Detection with the Fermi-Large Area Telescope
• Tidal Stripping in the Adiabatic Limit
• Spectral and spatial analysis of the dark matter subhalo candidates among Fermi Large Area Telescope unidentified sources
• SatGen -- II. Assessing the impact of a disc potential on subhalo populations
• Baryonic effects on the detectability of annihilation radiation from dark matter subhaloes around the Milky Way
• The Turn-Down of the Baryonic Tully-Fisher Relation and Changing Baryon Fractions at Low Galaxy Masses
• Pushing down the low-mass halo concentration frontier with the Lomonosov cosmological simulations
• The dark side of FIRE: predicting the population of dark matter subhaloes around Milky Way-mass galaxies
• Remnants of Galactic subhalos and their impact on indirect dark matter searches
• Shedding light on low-mass subhalo survival and annihilation luminosity with numerical simulations
• Investigating the detection of dark matter subhalos as extended sources with Fermi-LAT
• Sensitivity of the Cherenkov Telescope Array to dark subhalos
• Gamma-ray sensitivity to dark matter subhalo modelling at high latitudes
• The Impact of Molecular Hydrogen Cooling on the Galaxy Formation Threshold
• Star Streams in Triaxial Isochrone Potentials with Sub-Halos
• Spatial extension of dark subhalos as seen by Fermi-LAT and implications for WIMP constraints
• The viability of low-mass subhaloes as targets for gamma-ray dark matter searches
• New insights on low-mass dark matter subhalo tidal tracks via numerical simulations

Cited by in corpus (1)

• Deeper analysis of Fermi-LAT unassociated 4FGL J2112.5-3043 for possible identification