Primordial black hole constraints for curvaton models with predicted large non-Gaussianity

TL;DR

This paper investigates how non-Gaussian curvature perturbations in the early Universe influence primordial black hole formation, showing that constraints on perturbation amplitudes vary significantly with perturbation shape, especially in curvaton models.

Contribution

It demonstrates the strong dependence of PBH constraints on perturbation shape and provides specific calculations for curvaton models with large non-Gaussianity.

Findings

PBH constraints can deviate by two orders of magnitude from Gaussian limits.

The shape of perturbations critically affects PBH formation thresholds.

Curvaton models with large non-Gaussianity alter PBH mass spectra and constraints.

Abstract

We consider the early Universe scenario which allows for production of non-Gaussian curvature perturbations at small scales. We study the peculiarities of a formation of primordial black holes (PBHs) connected with the non-Gaussianity. In particular, we show that PBH constraints on the values of curvature perturbation power spectrum amplitude are strongly dependent on the shape of perturbations and can significantly (by two orders of magnitude) deviate from the usual Gaussian limit ${\cal P}_\zeta \lesssim 10^{-2}$. We give examples of PBH mass spectra calculations and PBH constraints for the particular case of the curvaton model.