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arXiv · 2009.10327

NANOGrav results and Dark First Order Phase Transitions

Andrea Addazi·Yi-Fu Cai·Qingyu Gan·Antonino Marciano·Kaiqiang Zeng
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Abstract

The recent NANOGrav evidence of a common-source stochastic background provides a hint to Gravitational Waves (GW) radiation from the Early Universe. We show that this result can be interpreted as a GW spectrum produced from First Order Phase Transitions (FOPTs) around a temperature in the KeV-MeV window. Such a class of FOPTs at temperatures much below the electroweak scale can be naturally envisaged in several Warm Dark Matter models such as Majoron Dark Matter.

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Andrea Addazi, Yi-Fu Cai, Qingyu Gan, Antonino Marciano, Kaiqiang Zeng. 2020-09-22. NANOGrav results and Dark First Order Phase Transitions. https://doi.org/10.1007/s11433-021-1724-6

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