A Novel Scheme for Dark Matter Annihilation Feedback in Cosmological
  Simulations
  We present a new self-consistent method for incorporating dark matter
annihilation feedback (DMAF) in cosmological N-body simulations. The power
generated by DMAF is evaluated at each dark matter (DM) particle which allows
for flexible energy injection into the surrounding gas based on the specific DM
annihilation model under consideration. Adaptive, individual time steps for gas
and DM particles are supported and a new time-step limiter, derived from the
propagation of a Sedov--Taylor blast wave, is introduced. We compare this
donor-based approach with a receiver-based approach used in recent studies and
illustrate the differences by means of a toy example. Furthermore, we consider
an isolated halo and a cosmological simulation and show that for these
realistic cases, both methods agree well with each other. The extension of our
implementation to scenarios such as non-local energy injection,
velocity-dependent annihilation cross-sections, and DM decay is
straightforward.
