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arXiv · 2101.09255

An allowed window for heavy neutral leptons below the kaon mass

Kyrylo Bondarenko·Alexey Boyarsky·Juraj Klaric·Oleksii Mikulenko·Oleg Ruchayskiy·Vsevolod Syvolap·Inar Timiryasov
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Abstract

The extension of the Standard Model with two gauge-singlet Majorana fermions can simultaneously explain two beyond-the-Standard-model phenomena: neutrino masses and oscillations, as well as the origin of the matter-antimatter asymmetry in the Universe. The parameters of such a model are constrained by the neutrino oscillation data, direct accelerator searches, big bang nucleosynthesis, and requirement of successful baryogenesis. We show that the combination of all these constraints still leaves an allowed region in the parameter space below the kaon mass. This region can be probed by the further searches of NA62, DUNE, or SHiP experiments.

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Kyrylo Bondarenko, Alexey Boyarsky, Juraj Klaric, Oleksii Mikulenko, Oleg Ruchayskiy, Vsevolod Syvolap, Inar Timiryasov. 2021-01-22. An allowed window for heavy neutral leptons below the kaon mass. https://doi.org/10.1007/jhep07(2021)193

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