Formation of primordial black holes in an axionlike curvaton model

TL;DR

This paper investigates how an axionlike curvaton model with inflaton coupling can produce primordial black holes that account for observed black hole binaries and dark matter, while satisfying current observational constraints.

Contribution

It provides a detailed analysis of PBH formation in an axionlike curvaton model, including effects of non-Gaussianity and window function choices, and assesses observational constraints.

Findings

The model can produce PBHs of $\,30 M_{\, ext{sun}}$ and $10^{-12} M_{\, ext{sun}}$.

The PBH spectrum can satisfy current observational constraints.

The model's predictions are consistent with gravitational wave and dark matter observations.

Abstract

We performed the detailed analysis of the primordial black hole (PBH) formation mechanism in an axionlike curvaton model with a coupling to inflaton. The phase direction of the complex scalar works as a curvaton and produces enough PBHs to explain the black hole binaries ($\sim 30 M_{\odot}$) observed in the LIGO-Virgo Collaboration or PBHs as dark matter (DM) ($\sim 10^{-12} M_{\odot}$). We examine whether our model satisfies the current constraints on the PBH mass spectrum, the curvature perturbation and the secondarily produced gravitational waves. We also take into account ambiguity about the choice of the window functions and effect of the non-Gaussianity.