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arXiv · 1906.10136

Possible Hints of Sterile Neutrinos in Recent Measurements of the Hubble Parameter

Graciela B. Gelmini·Alexander Kusenko·Volodymyr Takhistov
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Abstract

Local Universe observations find a value of the Hubble constant $H_0$ that is larger than the value inferred from the Cosmic Microwave Background and other early Universe measurements, assuming known physics and the $\Lambda$CDM cosmological model. We show that additional radiation in active neutrinos produced just before Big Bang Nucleosynthesis by an unstable sterile neutrino with mass $m_s=$ O(10) MeV can alleviate this discrepancy. The necessary masses and couplings of the sterile neutrino, assuming it mixes primarily with $\nu_{\tau}$ and/or $\nu_{\mu}$ neutrinos, are within reach of Super-Kamiokande as well as upcoming laboratory experiments such as NA62 and DUNE.

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Graciela B. Gelmini, Alexander Kusenko, Volodymyr Takhistov. 2019-06-24. Possible Hints of Sterile Neutrinos in Recent Measurements of the Hubble Parameter. https://doi.org/10.1088/1475-7516%2F2021%2F06%2F002

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