The dwarf galaxy DDO 47 as a dark matter laboratory: testing cusps hiding in triaxial halos

Abstract

We present an analysis of high resolution HI data of the dwarf galaxy DDO 47, aimed at testing the hypothesis that dark halo triaxiality might induce non-circular motions resulting in rotation curves best fitted by cored halos, even if the dark matter halo is intrinsically cuspy. This hypothesis could be invoked in order to reconcile the predictions of the standard LambdaCDM theory with the rotation curves of disk galaxies. DDO 47 is an ideal case to test this hypothesis because it has a very regular velocity field, its rotation curve is best fitted by a cored halo and a NFW halo is inconsistent with the data. We analysed the velocity field through the higher-order harmonic terms in order to search for kinematical signatures of alleged non-circular motions needed to "hide" a cusp: the result is that globally non-circular motions are at a level of 2-3 km/s, and they are more likely to be associated to the presence of some spiral structure than to a global elongated potential (e.g. a triaxial halo). These non-circular motions are far from being sufficient to account for the discrepancy with the LambdaCDM predictions. We therefore conclude that the dark matter halo around the dwarf galaxy DDO 47 is truly cored and that a cusp cannot be hidden by non-circular motions.

4 pages, accepted for publication in ApJ Letters, substantial changes from original version

References in corpus (22)

• A Universal Density Profile from Hierarchical Clustering
• The Structure of Cold Dark Matter Halos
• The Structure of Dark Matter Haloes in Dwarf Galaxies
• Cold collapse and the core catastrophe
• Concentrations of Dark Halos from their Assembly Histories
• The Inner Structure of LambdaCDM Halos III: Universality and Asymptotic Slopes
• The Inner Structure of LambdaCDM Halos I: A Numerical Convergence Study
• Response of dark matter halos to condensation of baryons: cosmological simulations and improved adiabatic contraction model
• Observational and Theoretical Constraints on Singular Dark Matter Halos
• H alpha rotation curves of Low Surface Brightness galaxies
• The cored distribution of dark matter in spiral galaxies
• Dark Matter Scaling Relations
• The Effect of Gas Cooling on the Shapes of Dark Matter Halos
• Measuring non-axisymmetry in spiral galaxies
• A Universal Density Profile for Dark and Luminous Matter?
• A High-Resolution Rotation Curve of NGC 6822: A Test-case for Cold Dark Matter
• New Light on Dark Matter
• A Search for Kinematic Evidence of Radial Gas Flows in Spiral Galaxies
• The constant density region of the dark halos of spiral galaxies
• The rotation curves of dwarf galaxies: a problem for Cold Dark Matter?
• Cores of Dark Matter Halos Correlate with Disk Scale Lengths
• The Distribution of Dark Matter in Galaxies: a Constant-Density Halo around DDO 47

Cited by in corpus (130)

• Dark Matter Self-interactions and Small Scale Structure
• High-Resolution Rotation Curves and Galaxy Mass Models from THINGS
• The Core-Cusp Problem
• Concentration, Spin and Shape of Dark Matter Haloes as a Function of the Cosmological Model: WMAP1, WMAP3 and WMAP5 results
• Mass-radius relation of Newtonian self-gravitating Bose-Einstein condensates with short-range interactions: I. Analytical results
• Ultra-Light Dark Matter
• Hidden Charged Dark Matter
• The dark matter density at the Sun's location
• A constant dark matter halo surface density in galaxies
• Stellar Feedback in Dwarf Galaxy Formation
• The Universal Rotation Curve of Spiral Galaxies. II The Dark Matter Distribution out to the Virial Radius
• Mass Models for Low Surface Brightness Galaxies with High Resolution Optical Velocity Fields
• The distribution of dark matter in galaxies
• Cosmological puzzle resolved by stellar feedback in high redshift galaxies
• High-resolution dark matter density profiles of THINGS dwarf galaxies: Correcting for non-circular motions
• The central slope of dark matter cores in dwarf galaxies: Simulations vs. THINGS
• Mass-radius relation of Newtonian self-gravitating Bose-Einstein condensates with short-range interactions: II. Numerical results
• On the frequency, intensity and duration of starburst episodes triggered by galaxy interactions and mergers
• NGC 3741: dark halo profile from the most extended rotation curve
• Constraints on the Dark Matter Particle Mass from the Number of Milky Way Satellites
• Erasing Dark Matter Cusps in Cosmological Galactic Halos with Baryons
• Dark Matter Candidates: A Ten-Point Test
• A wide-field HI mosaic of Messier 31. II.The disk warp, rotation and the dark matter halo
• Analysis of Rotation Curves in the framework of R^n gravity
• Empirical Models for Dark Matter Halos. II. Inner profile slopes, dynamical profiles, and rho/sigma^3
• Universality of galactic surface densities within one dark halo scale-length
• Searching for a Cosmological Preferred Axis: Union2 Data Analysis and Comparison with Other Probes
• Dynamical Centers and Non-Circular Motions in THINGS Galaxies: Implications for Dark Matter Halos
• Detecting dark matter WIMPs in the Draco dwarf: a multi-wavelength perspective
• Dwarf spheroidal galaxy kinematics and spiral galaxy scaling laws
• The universal rotation curve of dwarf disk galaxies
• Analytical properties of Einasto dark matter haloes
• The Distribution of Dark Matter Over 3 Decades in Radius in the Lensing Cluster Abell 611
• The PN.S Elliptical Galaxy Survey: the dark matter in NGC 4494
• The Dynamical and Chemical Evolution of Dwarf Spheroidal Galaxies
• Dwarf Galaxy Dark Matter Density Profiles Inferred from Stellar and Gas Kinematics
• Insight into the baryon-gravity relation in galaxies
• An extensive study of dynamical friction in dwarf galaxies: the role of stars, dark matter, halo profiles and MOND
• On the kinematic detection of accreted streams in the Gaia era: a cautionary tale
• The Rotation Velocity Attributable to Dark Matter at Intermediate Radii in Disk Galaxies
• On the Structure of Dark Matter Halos at the Damping Scale of the Power Spectrum with and without Relict Velocities
• Lopsided Spiral Galaxies
• Weak Lensing by Galaxies in Groups and Clusters: I.--Theoretical Expectations
• The Case Against Warm or Self-Interacting Dark Matter as Explanations for Cores in Low Surface Brightness Galaxies
• The PN.S Elliptical Galaxy Survey: a standard LCDM halo around NGC 4374?
• The Dynamical and Chemical Evolution of Dwarf Spheroidal Galaxies with GEAR
• Hiding Cusps in Cores: Kinematics of Disk Galaxies in Triaxial Dark Matter Halos
• Declining rotation curves of galaxies as a test of gravitational theory
• On the dark matter profile in Sculptor: Breaking the $\beta$ degeneracy with Virial shape parameters
• Dynamical signatures of a LCDM-halo and the distribution of the baryons in M33
• Sub-GeV dark matter as pseudo-Goldstone from the seesaw scale
• Recovering cores and cusps in dark matter haloes using mock velocity field observations
• Collisionally Regenerated Dark Matter Structures in Galactic Nuclei
• Clustering properties of a sterile neutrino dark matter candidate
• Constraining the NFW Potential with Observations and Modeling of LSB Galaxy Velocity Fields
• Pressure Support in Galaxy Disks: Impact on Rotation Curves and Dark Matter Density Profiles
• Velocity Dependence from Resonant Self-Interacting Dark Matter
• LambdaCDM Halo Density Profiles: where do actual halos converge to NFW ones?
• Extracting limits on Dark Matter annihilation from gamma-ray observations towards dwarf spheroidal galaxies
• Models of dark matter halos based on statistical mechanics: I. The classical King model
• Small scale aspects of warm dark matter : power spectra and acoustic oscillations
• A robust estimate of the Milky Way mass from rotation curve data
• Self-consistent models of cuspy triaxial galaxies with dark matter haloes
• The universal rotation curve of low surface brightness galaxies IV: the interrelation between dark and luminous matter
• Computational issues in chemo-dynamical modelling of the formation and evolution of galaxies
• Gravity Modification with Yukawa-type Potential: Dark Matter and Mirror Gravity
• Dark matter dynamics in Galactic center
• The distribution of globular clusters in kinematic spaces does not trace the accretion history of the host galaxy
• Evidences against cuspy dark matter halos in large galaxies
• Gas dynamics in dwarf galaxies as testbeds for dark matter and galaxy evolution
• The bar pattern speed of NGC 4431
• Self-interacting dark matter without prejudice
• The Structure of Rapidly Rotating Late-Type Spiral Galaxies: I. Photometry, HI and Optical Kinematics
• The dark matter halos of the bluest low surface brightness galaxies
• A High-Resolution Study of the HI Content of Local Group Dwarf Irregular Galaxy WLM
• The Disk Mass of Spiral Galaxies
• On the isolated dwarf galaxies: from cuspy to flat dark matter density profiles and metallicity gradients
• Non-circular motions and the cusp-core discrepancy in dwarf galaxies
• Mirror Matter, Mirror Gravity and Galactic Rotational Curves
• Constraints on interacting dark energy models from galaxy Rotation Curves
• Mass models from high-resolution HI data of the dwarf galaxy NGC 1560
• Generalized LTB model with Inhomogeneous Isotropic Dark Energy: Observational Constraints
• Modified gravity models and the central cusp of dark matter halos in galaxies
• Remarks on the properties of elliptical galaxies in modified Newtonian dynamics
• Simulations of galactic disks including a dark baryonic component
• The Dark Matter Distribution in the Spiral $NGC3198$ out to 0.22 $R_{vir}$
• Strongly Coupled Dark Energy Cosmologies: preserving LCDM success and easing low scale problems II - Cosmological simulations
• Structural properties of non-spherical dark halos in Milky Way and Andromeda dwarf spheroidal galaxies
• MOND and the Universal Rotation Curve: similar phenomenologies
• Detected fluctuations in SDSS LRG magnitudes: Bulk flow signature or systematic?
• The Mutual Interaction Between Population III Stars and Self-Annihilating Dark Matter
• Free streaming in mixed dark matter
• Dark Matter in Galaxies: evidences and challenges
• Formation of Dark Matter Torii Around Supermassive Black Holes Via The Eccentric Kozai-Lidov Mechanism
• Asymmetric mass models of disk galaxies - I. Messier 99
• DM haloes in the fifth-force cosmology
• Sterile neutrinos produced near the EW scale I: mixing angles, MSW resonances and production rates
• The degeneracy between star-formation parameters in dwarf galaxy simulations and the Mstar-Mhalo relation
• Warm dark matter at small scales: peculiar velocities and phase space density
• Leak-in Dark Matter
• Dark matter in disk galaxies I: a Markov Chain Monte Carlo method and application to DDO 154
• Interaction between collisionless galactic discs and nonaxissymmetric dark matter haloes
• Testing the minimum variance method for estimating large-scale velocity moments
• The mass distribution in Spirals
• Neutrinos as galactic dark matter in the Ursa Major galaxy group?
• The structure of spiral galaxies: radial profiles in stellar Mass-to-Light ratio and the Dark Matter distribution
• The radial dependence of dark matter distribution in M33
• The dark matter halo density profile, spiral arm morphology and black hole mass of M33
• Effect of Population III Multiplicity on Dark Star Formation
• Testing baryon-induced core formation in $\Lambda$CDM: A comparison of the DC14 and coreNFW dark matter halo models on galaxy rotation curves
• Cusp-core problem and strong gravitational lensing
• keV Warm Dark Matter via the Supersymmetric Higgs Portal
• A common surface-density scale for the Milky Way and Andromeda dwarf satellites as a constraint on dark matter models
• Testing the Newton second law in the regime of small accelerations
• Do High-Velocity Clouds trace the Dark Matter subhalo population?
• The Distribution of Mass in the Orion Dwarf Galaxy
• DM particles: how warm they can be?
• A spherical scalar-tensor galaxy model
• Rotation curves of galaxies and the stellar mass-to-light ratio
• Rotation Curves and Nonextensive Statistics
• Analysis of Rotation Curves in the Framework of the Gravitational Suppression Model
• Empirical velocity profiles for galactic rotation curves
• An analytical approach to the dwarf galaxies cusp problem
• The mass distribution in Spiral galaxies
• A cosmologically motivated description of the dark matter halo profile for the Low Surface Brightness Galaxy, Malin 1
• Gas engaged in noncircular motions in LITTLE THINGS dwarf irregular galaxies
• Dynamics of Starbursting Dwarf Galaxies. III. A HI study of 18 nearby objects
• End of a Dark Age?
• Cusped Mass Density Profiles and Magnification Ratios of Double Image Gravitational Lenses
• Dark Matter Universal Properties in Galaxies