NANOGrav results and LIGO-Virgo primordial black holes in axion-like curvaton model

TL;DR

This paper explores how an axion-like curvaton model can simultaneously explain the NANOGrav gravitational wave signals and the formation of primordial black holes relevant to LIGO-Virgo observations, highlighting the role of non-Gaussianity.

Contribution

It demonstrates that the axion-like curvaton model can account for both NANOGrav signals and LIGO-Virgo black hole events through scalar perturbations and non-Gaussian effects.

Findings

The model produces PBHs consistent with LIGO-Virgo events.

Non-Gaussianity suppresses induced GWs to match NANOGrav data.

Simultaneous explanation of GWs and PBHs is feasible within this framework.

Abstract

We discuss a possible connection between the recent NANOGrav results and the primordial black holes (PBHs) for the LIGO-Virgo events. In particular, we focus on the axion-like curvaton model, which provides a sizable amount of PBHs and GWs induced by scalar perturbations around the NANOGrav frequency range. The inevitable non-Gaussianity of this model suppresses the induced GWs associated with PBHs for the LIGO-Virgo events to be compatible with the NANOGrav results. We show that the axion-like curvaton model can account for PBHs for the LIGO-Virgo events and the NANOGrav results simultaneously.