Effect of small scale density perturbations on the formation of dark matter halo profiles

Abstract

With help of a set of toy N-body models of dark halo formation we study the impact of small scale initial perturbations on the inner density profiles of haloes. We find a significant flattening of the inner slope $\alpha={d \log \rho \over d \log r}$ to $\alpha=-0.5$ in some range of scales and amplitudes of the perturbations (while in the case of absence of these perturbations the NFW profile with $\alpha=-1$ is reproduced). This effect may be responsible for the formation of cuspless galactic haloes.Comment: 5 pages, 2 figures, accepted for publication in MNRAS Letter