Determining the Nature of Dark Matter with Astrometry

Abstract

We show that measurements of stellar proper motions in dwarf spheroidal galaxies provide a powerful probe of the nature of dark matter. Allowing for general dark matter density profiles and stellar velocity anisotropy profiles, we show that the log-slope of the dark matter profile at about twice the stellar core (King) radius can be measured to within \pm 0.2 when the proper motions of 200 stars are added to standard line-of-sight velocity dispersion data. This measurement of the log-slope provides a test of Cold and Warm Dark Matter theories at a sensitivity not possible with line-of-sight velocity dispersion measurements alone. The upcoming SIM PlanetQuest will have the sensitivity to obtain the required number of proper motions in Milky Way dwarf spheroidal galaxies.

arXiv commentAccepted for publication in ApJL

References in corpus (13)

• The Structure of Cold Dark Matter Halos
• The Structure of Dark Matter Haloes in Dwarf Galaxies
• Substructure and halo density profiles in a Warm Dark Matter Cosmology
• High-Resolution Measurements of the Halos of Four Dark Matter-Dominated Galaxies: Deviations from a Universal Density Profile
• Density Profiles of Cold Dark Matter Substructure: Implications for the Missing Satellites Problem
• Cusps in CDM halos
• Halo Cores and Phase Space Densities: Observational Constraints on Dark Matter Physics and Structure Formation
• Dark Matter from Early Decays
• High Resolution Optical Velocity Fields of 11 Low Surface Brightness Galaxies
• SuperWIMP Solutions to Small Scale Structure Problems
• Exploring Halo Substructure with Giant Stars: The Velocity Dispersion Profiles of the Ursa Minor and Draco Dwarf Spheroidals At Large Angular Separations
• Dark Matter in Dwarf Spheroidals I: Models
• Dark matter distribution in the Draco dwarf from velocity moments

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