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arXiv · 2206.05186

Improved cosmological bounds for a fine-tuned see-saw mechanism of keV sterile neutrinos

M. N. Dubinin·D. M. Kazarkin
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Abstract

Considering the gauge model SU(2)_L x U(1) with the extension of the lepton sector by right-handed sterile Majorana neutrinos, we distinguish a "minimal parametric mixing scenario" for a complete matrix of 6 x 6 light (active) and sterile neutrinos, which depends, in addition to experimentally measured physical parameters, only on the masses of sterile neutrinos. For such a scenario, improved cosmological bounds are provided, resulting from the lifetime of sterile neutrinos and the fraction of energy carried by sterile neutrino dark matter.

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M. N. Dubinin, D. M. Kazarkin. 2022-06-10. Improved cosmological bounds for a fine-tuned see-saw mechanism of keV sterile neutrinos. https://arxiv.org/abs/2206.05186

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