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arXiv · 2002.00036

Degenerate Sub-keV Fermion Dark Matter from a Solution to the Hubble Tension

Gongjun Choi·Motoo Suzuki·Tsutomu T. Yanagida
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Abstract

We present a dark sector model addressing both the Hubble tension and the core-cusp problem. The model is based on a hidden Abelian gauge symmetry group with some chiral fermions required by the anomaly cancellation conditions, producing a candidate for the decaying fermion dark matter as a solution to the Hubble tension. Moreover, the sub-keV mass regime and the thermal history of the dark sector help the dark matter candidate resolve the core-cusp problem occurring in the standard $\Lambda$CDM cosmology.

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Gongjun Choi, Motoo Suzuki, Tsutomu T. Yanagida. 2020-01-31. Degenerate Sub-keV Fermion Dark Matter from a Solution to the Hubble Tension. https://doi.org/10.1103/physrevd.101.075031

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