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arXiv · 2501.11619

Supercooled phase transitions in conformal dark sectors explain NANOGrav data

João Gonçalves·Danny Marfatia·António P. Morais·Roman Pasechnik
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Abstract

According to recent lore, it is difficult to explain the evidence for a stochastic gravitational wave background obtained by pulsar timing arrays with supercooled first-order phase transitions (FOPTs). We demonstrate that supercooled FOPTs in dark U(1)' models with a conformal dark sector easily explain the nHz signal at NANOGrav.

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João Gonçalves, Danny Marfatia, António P. Morais, Roman Pasechnik. 2025-01-20. Supercooled phase transitions in conformal dark sectors explain NANOGrav data. https://doi.org/10.1016/j.physletb.2025.139829

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