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

Abstract

With the 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 α = d log ρ| d log r to α = -0.5 in some range of scales and amplitudes of the perturbations (while in the case of absence of these perturbations, the Navarro-Frenk- White profile with α = -1 is reproduced). This effect may be responsible for the formation of cuspless galactic haloes. © 2012 The Authors. Monthly Notices of the Royal Astronomical Society © 2012 RAS.