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arXiv · 2009.08268

NANOGrav Hints to Primordial Black Holes as Dark Matter

V. De Luca·G. Franciolini·A. Riotto
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Abstract

The NANOGrav Collaboration has recently published a strong evidence for a stochastic common-spectrum process that may be interpreted as a stochastic gravitational wave background. We show that such a signal can be explained by second-order gravitational waves produced during the formation of primordial black holes from the collapse of sizeable scalar perturbations generated during inflation. This possibility has two predictions: $i$) the primordial black holes may comprise the totality of the dark matter with the dominant contribution to their mass function falling in the range $(10^{-15}\div 10^{-11}) M_\odot$ and $ii$) the gravitational wave stochastic background will be seen as well by the LISA experiment.

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V. De Luca, G. Franciolini, A. Riotto. 2020-09-17. NANOGrav Hints to Primordial Black Holes as Dark Matter. https://doi.org/10.1103/physrevlett.126.041303

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