Joint Astrophysics Colloquium

The Biggest Dark Matter Halos

Neal Dalal

CITA

The rarest, most massive dark matter halos are paradoxically the hardest to simulate numerically and the easiest to understand theoretically. I will describe how many aspects of massive halos may be understood using simple, self-similar collapse models. Combined with the (known) statistics of Gaussian random fields, this model makes predictions for the abundance and clustering of massive halos, with no adjustable parameters. This allows us to extend theoretical predictions for the halo mass function into regimes already probed by ongoing cluster surveys, beyond the range of N-body simulations.