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arXiv · 2312.15435

Constraints on sterile neutrinos and the cosmological tensions

Supriya Pan·Osamu Seto·Tomo Takahashi·Yo Toda
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Abstract

We investigate cosmological bounds on sterile neutrino masses in the light of the Hubble and $S_8$ tensions. We argue that non-zero masses for sterile neutrinos are inferred at 2$\sigma$ level in some extended models such as varying dark energy equation of state, when a direct measurement of the Hubble constant $H_0$ and weak lensing measurement of dark energy survey (DES) are taken into account. Furthermore, the Hubble and $S_8$ tensions are also reduced in such a framework. We also consider the case where a non-flat Universe is allowed and show that a slightly open Universe may be favored in models with sterile neutrinos in the context of the cosmological tensions.

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Supriya Pan, Osamu Seto, Tomo Takahashi, Yo Toda. 2023-12-24. Constraints on sterile neutrinos and the cosmological tensions. https://doi.org/10.1103/physrevd.110.083524

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