Presentation #405.03 in the session Analysis of equilibrium collisionless systems: power and peril.
One major source of disequilibrium in the Milky Way is its most massive satellite, the LMC. Kinematics of distant halo tracers show a velocity dipole in the Milky Way halo, which has been interpreted using N-body simulations as the LMC inducing a reflex motion in the Milky Way disk. In this talk, I discuss applying this framework to more realistic halos comprised of substructure from the FIRE-2 zoom-in cosmological simulations. Velocity dipoles are resolved in Milky Way-mass hosts experiencing an LMC-like interaction and evolve in a manner consistent with a two-body interaction between the stellar disk and the LMC analog. However, satellite galaxies and stellar streams can create velocity dipoles in systems that aren’t experiencing a major satellite accretion, suggesting that care must be taken to remove substructure in the Milky Way observations.