Dark Matter Direct Search Rates in Simulations of the Milky Way and Sagittarius Stream

Abstract

We analyze self-consistent N-body simulations of the Milky Way disk and the ongoing disruption of the Sagittarius dwarf satellite to study the effect of Sagittarius tidal debris on dark matter detection experiments. In agreement with significant previous work, we reiterate that the standard halo model is insufficient to describe the non-Maxwellian velocity distribution of the Milky Way halo in our equilibrium halo-only and halo/galaxy models, and offer suggestions for correcting for this discrepancy. More importantly, we emphasize that the dark matter component of the leading tidal arm of the Sagittarius dwarf is significantly more extended than the stellar component of the arm, since the dark matter and stellar streams are not necessarily coaxial and may be offset by several kpc at the point at which they impact the Galactic disk. This suggests that the dark matter component of the Sagittarius debris is likely to have a non-negligible influence on dark matter detection experiments even when the stellar debris is centered several kpc from the solar neighborhood. Relative to models without an infalling Sagittarius dwarf, the Sagittarius dark matter debris in our models induces an energy-dependent enhancement of direct search event rates of as much as ~20 - 45%, an energy-dependent reduction in the amplitude of the annual modulation of the event rate by as much as a factor of two, a shift in the phase of the annual modulation by as much as ~20 days, and a shift in the recoil energy at which the modulation reverses phase. These influences of Sagittarius are of general interest in the interpretation of dark matter searches, but may be particularly important in the case of relatively light (m_X < 20 GeV) dark matter because the Sagittarius stream impacts the solar system at high speed compared to the primary halo dark matter.

arXiv comment24 pages, 5 figures; to appear in JCAP; revised to reflect referee's comments

References in corpus (69)

• The Structure of Cold Dark Matter Halos
• Particle Dark Matter: Evidence, Candidates and Constraints
• Supersymmetric Dark Matter
• Local Kinematics and the Local Standard of Rest
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: I. Morphology of the Sagittarius Core and Tidal Arms
• Response of dark matter halos to condensation of baryons: cosmological simulations and improved adiabatic contraction model
• The Field of Streams: Sagittarius and its Siblings
• New results from DAMA/LIBRA
• Results from a Search for Light-Mass Dark Matter with a P-type Point Contact Germanium Detector
• Results from 730 kg days of the CRESST-II Dark Matter Search
• Cuspy No More: How Outflows Affect the Central Dark Matter and Baryon Distribution in Lambda CDM Galaxies
• Debris streams in the solar neighbourhood as relicts from the formation of the Milky Way
• The Sagittarius Dwarf Galaxy: a Model for Evolution in a Triaxial Milky Way Halo
• Connecting Galaxies, Halos, and Star Formation Rates Across Cosmic Time
• The Aquila comparison Project: The Effects of Feedback and Numerical Methods on Simulations of Galaxy Formation
• The dark matter density at the Sun's location
• Compatibility of DAMA/LIBRA dark matter detection with other searches
• Internal and External Alignment of the Shapes and Angular Momenta of LCDM Halos
• Velocity and spatial biases in CDM subhalo distributions
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: IV. Modeling the Sagittarius Tidal Tails
• The Formation and Survival of Discs in a Lambda-CDM Universe
• The Milky Way: An Exceptionally Quiet Galaxy; Implications for the formation of spiral galaxies
• The Sagittarius impact as an architect of spirality and outer rings in the Milky Way
• The local surface density of disc matter mapped by Hipparcos
• Dark Matter Direct Detection with Non-Maxwellian Velocity Structure
• Velocity trends in the debris of Sagittarius and the shape of the dark-matter halo of the Galaxy
• Phase-space structure in the local dark matter distribution and its signature in direct detection experiments
• Dynamical Blueprints for Galaxies
• Halo expansion in cosmological hydro simulations: towards a baryonic solution of the cusp/core problem in massive spirals
• Semiconductor Probes of Light Dark Matter
• The Causes of Halo Shape Changes Induced by Cooling Baryons: Disks Versus Substructures
• The Astrophysical Uncertainties Of Dark Matter Direct Detection Experiments
• Integrating Out Astrophysical Uncertainties
• Annual Modulation of Dark Matter in the Presence of Streams
• A Two Micron All-Sky Survey View of the Sagittarius Dwarf Galaxy: II. Swope Telescope Spectroscopy of M Giant Stars in the Dynamically Cold Sagittarius Tidal Stream
• Spin-independent elastic WIMP scattering and the DAMA annual modulation signal
• Model Independent Form Factors for Spin Independent Neutralino-Nucleon Scattering from Elastic Electron Scattering Data
• The Effects of the Sagittarius Dwarf Tidal Stream on Dark Matter Detectors
• Re-Assembling the Sagittarius Dwarf Galaxy
• Detectability of Weakly Interacting Massive Particles in the Sagittarius Dwarf Tidal Stream
• The Dark Matter at the End of the Galaxy
• Dark Matter Direct Detection Signals inferred from a Cosmological N-body Simulation with Baryons
• Galactic Halo Models and Particle Dark-Matter Detection
• Astrophysical uncertainties on direct detection experiments
• A dark matter disc in three cosmological simulations of Milky Way mass galaxies
• The phase-space structure of a dark-matter halo: Implications for dark-matter direct detection experiments
• The Dark Disk of the Milky Way
• Toward A Consistent Picture For CRESST, CoGeNT and DAMA
• Direct Detection of Dark Matter Debris Flows
• The Destruction of Thin Stellar Disks Via Cosmologically Common Satellite Accretion Events
• Is the sky falling? Searching for stellar streams in the local Milky Way disc in the CORAVEL and RAVE surveys
• Reconstructing WIMP Properties in Direct Detection Experiments Including Galactic Dark Matter Distribution Uncertainties
• DAMA and CoGeNT without astrophysical uncertainties
• Global fits of the cMSSM including the first LHC and XENON100 data
• Using the Energy Spectrum at DAMA/LIBRA to Probe Light Dark Matter
• The impact of going beyond the Maxwell distribution in direct dark matter detection rates
• WIMP astronomy and particle physics with liquid-noble and cryogenic direct-detection experiments
• Implications of CoGeNT's New Results For Dark Matter
• The Northern wraps of the Sagittarius Stream as traced by Red Clump stars: distances, intrinsic widths and stellar densities
• Progressively more prolate dark matter halo in the outer Galaxy as traced by flaring HI gas
• The Phase of the Annual Modulation as a Tool for Determining the WIMP Mass
• The velocity anisotropy - density slope relation
• Is the Dark Disc contribution to Dark Matter Signals important ?
• Probing dark matter streams with CoGeNT
• Dark Matter Search with sub-keV Germanium Detectors at the China Jinping Underground Laboratory
• Debris Flows in Direct Dark Matter Searches-The modulation effect
• CDMS-II to SuperCDMS: WIMP search at a zeptobarn
• Low-Mass WIMP Sensitivity and Statistical Discrimination of Electron and Nuclear Recoils by Varying Luke-Neganov Phonon Gain in Semiconductor Detectors
• Dark Matter Debris Flows in the Milky Way

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• Annual Modulation of Dark Matter: A Review
• A review of the discovery reach of directional Dark Matter detection
• Revealing the Dark Matter Halo with Axion Direct Detection
• A Next-Generation Liquid Xenon Observatory for Dark Matter and Neutrino Physics
• Halo-to-Halo Similarity and Scatter in the Velocity Distribution of Dark Matter
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• Quenching and Channeling of Nuclear Recoils in NaI[Tl]: Implications for Dark Matter Searches
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• Under the Firelight: Stellar Tracers of the Local Dark Matter Velocity Distribution in the Milky Way
• Implications of hydrodynamical simulations for the interpretation of direct dark matter searches
• Via Machinae: Searching for Stellar Streams using Unsupervised Machine Learning
• Mapping the Monoceros Ring in 3D with Pan-STARRS1
• Directional detection of dark matter streams
• The highest-speed local dark matter particles come from the Large Magellanic Cloud
• Bracketing the impact of astrophysical uncertainties on local dark matter searches
• Reconstructing the three-dimensional local dark matter velocity distribution
• Extragalactic dark matter and direct detection experiments
• Light weakly interacting massive particles
• TASI 2014 Lectures: The Hunt for Dark Matter
• Informing dark matter direct detection limits with the ARTEMIS simulations
• Dark matter substructures affect dark matter-electron scattering in xenon-based direct detection experiments
• Prospects for detection of target-dependent annual modulation in direct dark matter searches
• The Milky Way, Coming into Focus: Precision Astrometry Probes its Evolution, and its Dark Matter
• Harmonics in the Dark-Matter Sky: Directional Detection in the Fourier-Bessel Basis
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• The Dynamical Response of Dark Matter to Galaxy Evolution Affects Direct-Detection Experiments
• Revisiting XENON100's Constraints (and Signals?) For Low-Mass Dark Matter
• Gravitational Focusing and Substructure Effects on the Rate Modulation in Direct Dark Matter Searches
• Structures induced by companions in galactic discs
• On the Origin of the Monoceros Ring - I: Kinematics, proper motions, and the nature of the progenitor
• Sliding into DM: Determining the local dark matter density and speed distribution using only the local circular speed of the Galaxy
• Weakly-Supervised Anomaly Detection in the Milky Way
• Search for the Sagittarius Tidal Stream of Axion Dark Matter around 4.55 $\mu$eV
• Constraints on dark matter interactions from the first results of DarkSide-50
• Probing light WIMPs with directional detection experiments
• Theoretical prospects for directional WIMP detection