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arXiv · 2011.01270

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

Keisuke Inomata·Masahiro Kawasaki·Kyohei Mukaida·Tsutomu T. Yanagida
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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.

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Keisuke Inomata, Masahiro Kawasaki, Kyohei Mukaida, Tsutomu T. Yanagida. 2021-04-06. NANOGrav results and LIGO-Virgo primordial black holes in axion-like curvaton model. https://doi.org/10.1103/physrevlett.126.131301

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