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arXiv · 1308.3550

Direct Search for Right-handed Neutrinos and Neutrinoless Double Beta Decay

Takehiko Asaka·Shintaro Eijima
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Abstract

We consider an extension of the Standard Model by two right-handed neutrinos, especially with masses lighter than charged $K$ meson. This simple model can realize the seesaw mechanism for neutrino masses and also the baryogenesis by flavor oscillations of right-handed neutrinos. We summarize the constraints on right-handed neutrinos from direct searches as well as the big bang nucleosynthesis. It is then found that the possible range for the quasi-degenerate mass of right-handed neutrinos is $M_N \geq 163 \MeV$ for normal hierarchy of neutrino masses, while $M_N = 188 \text{--} 269 \MeV$ and $M_N \geq 285 \MeV$ for inverted hierarchy case. Furthermore, we find in the latter case that the possible value of the Majorana phase is restricted for $M_N = 188 \text{--} 350 \MeV$, which leads to the fact that the rate of neutrinoless double beta decay is also limited.

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Takehiko Asaka, Shintaro Eijima. 2013-08-16. Direct Search for Right-handed Neutrinos and Neutrinoless Double Beta Decay. https://doi.org/10.1093/ptep/ptt094

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