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arXiv · 1508.02504

Sterile neutrinos with pseudoscalar self-interactions and cosmology

Maria Archidiacono·Steen Hannestad·Rasmus Sloth Hansen·Thomas Tram
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Abstract

Sterile neutrinos in the electronvolt mass range are hinted at by a number of terrestrial neutrino experiments. However, such neutrinos are highly incompatible with data from the Cosmic Microwave Background and large scale structure. This paper discusses how charging sterile neutrinos under a new pseudoscalar interaction can reconcile eV sterile neutrinos with terrestrial neutrino data. We show that this model can reconcile eV sterile neutrinos in cosmology, providing a fit to all available data which is way better than the standard $\Lambda$CDM model with one additional fully thermalized sterile neutrino. In particular it also prefers a value of the Hubble parameter much closer to the locally measured value.

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Maria Archidiacono, Steen Hannestad, Rasmus Sloth Hansen, Thomas Tram. 2015-08-11. Sterile neutrinos with pseudoscalar self-interactions and cosmology. https://doi.org/10.1103/physrevd.93.045004

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