Gemini dark matter
Year: 2024
Type: article
Abstract: The S 8 / σ 8 tension in the large-scale structure can be explained by decaying dark matter with an almost degenerate spectrum and small enough decay width. Here we propose the Gemini dark matter model, which contains a heavy mother particle χ 3 and two twins χ 1 / 2 , which are almost degenerate in mass and are produced at the same time. The dark sector is charged under the same Froggatt-Nielsen symmetry that can explain the hierarchy of the Standard Model Yukawa couplings. The slightly heavier χ 2 decays into χ 1 and the axionic component of the flavon, which washes out the small-scale structure and resolves S 8 / σ 8 tension. We present the production mechanism of Gemini dark matter and viable parameter regions. We find that, despite the preferred dark matter mass being O ( 1 ) – O ( 100 ) keV , they constitute cold dark matter. The Gemini dark matter model predicts an abundance of dark radiation that will be probed in future measurements of the cosmic microwave background. Published by the American Physical Society 2024
Authors: Andrew Cheek, Yu-Cheng Qiu, Liang Tan
Institution: Shanghai Jiao Tong University
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4403486337