Speaker
Description
Dark matter halos are self-gravitating objects seeded from small density perturbations in the early universe. Their structure can be described by a universal spherical averaged density profile across the scale of nearly all astronomical objects - the NFW profile - whose physical origin is not well understood. In recent N-body simulations, halos forming density profile as power-law with index -1.5 are found near the cut-off scale of the density perturbations, while analytical self-similar solution gives a power-law index of -12/7.
In this work, we investigate the evolution of the density profiles of 8 halos at high redshifts with 8 different cut-off scales in order to provide a more comprehensive picture of the relationship between halo structures and their initial perturbations, and tested the results against the theoretical predictions. Special attention is given to the validity of the self-similar assumption and attempts are made to understand the later convergence to NFW profile.
