Dark Matter and Galactic Dynamics - M. Walker (Cambridge)

Thursday 11 Jul 2013, 11:00 → 12:00 Europe/Paris

I will explain how to use the motions of stars to learn about the nature of particles. More specifically, I will translate the stellar kinematics observed in the nearest, smallest and "darkest" galaxies into a test of the standard hypothesis that dark matter consists of "cold" and "collisionless" (i.e., weakly interacting) particles. This model seems to require that baryon-driven processes (e.g., energetic feedback from supernova explosions) alter the internal structure of galactic dark matter halos systematically with respect to predictions derived from cosmological N-body simulations. I will identify future work -- both observational and theoretical -- that I expect will tell definitively whether such reconciliation is energetically feasible or whether the dark matter model requires additional complexity.

Transparents walker.pdf