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arXiv · 1705.04521

Gravitino/Axino as Decaying Dark Matter and Cosmological Tensions

Koichi Hamaguchi·Kazunori Nakayama·Yong Tang
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Abstract

In supersymmetric axion models, if the gravitino or axino is the lightest SUSY particle (LSP), the other is often the next-to-LSP (NLSP). We investigate the cosmology of such a scenario and point out that the lifetime of the NLSP naturally becomes comparable to the present age of the universe in a viable parameter region. This is a well-motivated example of the so-called decaying dark matter model, which is recently considered as an extension of the $\Lambda$CDM model to relax some cosmological tensions.

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Koichi Hamaguchi, Kazunori Nakayama, Yong Tang. 2017-05-12. Gravitino/Axino as Decaying Dark Matter and Cosmological Tensions. https://doi.org/10.1016/j.physletb.2017.06.071

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