The effect of non-Gaussian curvature perturbations on the formation of primordial black holes

This paper explores the consequences of non-Gaussian cosmological perturbations for the formation of primordial black holes (PBHs). A non-Gaussian probability distribution function (PDF) of curvature perturbations is presented with an explicit contribution from the three-point correlation function to linear order. The consequences of this non-Gaussian PDF for the large perturbations that form PBHs are then studied. Using the observational limits for the non-Gaussian parameter fNL, new bounds to the mean amplitude of curvature perturbations are derived in the range of scales relevant for PBH formation.