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arXiv · 2305.14242

Axion Poltergeist

Keisuke Harigaya·Keisuke Inomata·Takahiro Terada
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Abstract

Rotations of axion fields in the early universe can produce dark matter and the matter-antimatter asymmetry of the universe. We point out that the rotation can generate an observable amount of a stochastic gravitational-wave (GW) background. It can be doubly enhanced in a class of models in which the equation of state of the rotations rapidly changes from a non-relativistic matter-like one to a kination-like one by 1) the so-called poltergeist mechanism and 2) slower redshift of GWs compared to the axion kination fluid. In supersymmetric UV completion, future GW observations can probe the supersymmetry-breaking scale up to $10^7\,$GeV even if the axion does not directly couple to the Standard Model fields.

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Keisuke Harigaya, Keisuke Inomata, Takahiro Terada. 2023-05-23. Axion Poltergeist. https://doi.org/10.1103/physrevd.108.l081303

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