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arXiv · 2606.24109

Neutrinoless double $\beta$ decay and leptogenesis in seesaw model

Kazuo Fujikawa
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Abstract

The fermion $\nu_{R}+C\overline{\nu_{R}}^{T}$ in the Type I seesaw model, which is commonly identified with a Majorana fermion, is not a Majorana fermion and thus no neutrinoless double $\beta$ decay (in the case of $\nu_{L}-C\overline{\nu_{L}}^{T}$) due to the theorem on the absence of a Majorana-Weyl fermion in the representation of the d=4 Lorentz group. The leptogenesis is realized naturally together with the neutrinoless double $\beta$ decay by first defining C symmetric Majorana fermions in the seesaw model using an analogue of the Bogoliubov transformation.

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Kazuo Fujikawa. 2026-06-23. Neutrinoless double $\beta$ decay and leptogenesis in seesaw model. https://arxiv.org/abs/2606.24109

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