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arXiv · 2307.06757

PBHs and GWs from $\mathbb{T}^2$-inflation and NANOGrav 15-year data

Seyed Ali Hosseini Mansoori·Fereshteh Felegray·Alireza Talebian·Mohammad Sami
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Abstract

In this paper, we propose a novel mechanism in $\mathbb{T}^2$-inflation to enhance the power spectrum large enough to seed primordial black holes (PBHs) formation. To accomplish this, we consider the coupling function between the inflaton field and $\mathbb{T}^2= T_{μν}T^{μν}$ term. PBHs formed within this scenario can contribute partially or entirely to dark matter (DM) abundance. Furthermore, the amplification in the scalar power spectrum will concurrently produce significant scalar-induced gravitational waves (SIGWs) as a second-order effect. In addition, the energy spectrum associated with SIGWs can be compatible with the recent NANOGrav 15-year stochastic gravitational wave detection and fall into the sensitivity range of other forthcoming GW observatories.

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Seyed Ali Hosseini Mansoori, Fereshteh Felegray, Alireza Talebian, Mohammad Sami. 2023-08-17. PBHs and GWs from $\mathbb{T}^2$-inflation and NANOGrav 15-year data. https://arxiv.org/abs/2307.06757

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