Speaker
Description
Understanding the dark matter (DM) distribution within the inner few kpc of the Milky Way (MW) is essential to probe the particle nature of DM, and set the correct predictions for DM detection experiments. However, it is difficult to directly measure the density profile of DM in the inner galaxy, thus we rely on predictions from cosmological simulations.We characterize and compare the DM density profiles in the FIRE-2, Auriga, Vintergatan, and Illustris TNG50 simulations, investigating the effect of different subgrid models on the inner profile. We show that the DM density profile observed in Auriga, Vintergatan, and Illustris TNG50 can be modeled using the adiabatic contraction prescription of Gnedin et al. 2004, while FIRE-2 has a stronger feedback, leading to a break away from the adiabatic contraction prescription. We also show that spherical symmetry is a good approximation for the adiabatically-contracted DM profiles, while FIRE-2 predicts an ellipsoidal shape aligned with the disk within 10◦ of the galactic center. With the models calibrated to these simulations and using the observed properties of the MW’s stellar distribution, we are able to bracket the range of expected density profiles in the MW, and subsequently the DM annihilation flux for indirect detection.
