Shaken and Stirred: The Milky Way's Dark Substructures

Understand

The predicted abundance and properties of the low-mass substructures embedded inside larger dark matter haloes differ sharply among alternative dark matter models.

• Too small to host galaxies themselves, these subhaloes may still be detected via gravitational lensing, or via perturbations of the Milky Way's globular cluster streams and its stellar disk.
• Here we use the Apostle cosmological simulations to predict the abundance and the spatial and velocity distributions of subhaloes in the range 10^6.5-10^8.5 solar masses inside haloes of mass ~ 10^12 solar masses in LCDM.
• Although these subhaloes are themselves devoid of baryons, we find that baryonic effects are important.