We study a multi-localization model for charged leptons and neutrinos, including the possibility of a see-saw mechanism. This framework offers the opportunity to allow for realistic solutions in a consistent model without fine-tuning of parameters, even if quarks are also considered. Those solutions predict that the large Majorana mass eigenvalues for right-handed neutrinos are of the same order of magnitude, although this almost common mass can span a large range (bounded from above by $\sim 10^{ 12}{ \rm GeV}$). The model also predicts Majorana masses between $\sim 10^{ -2}{ \rm eV}$ and $\sim 5 \ 10^{ -2}{ \rm eV}$ for the left-handed neutrinos, both in the normal and inverted mass hierarchy cases. This mass interval corresponds to sensitivities which are reachable by proposed neutrinoless double $\beta$ decay experiments. The preferred range for leptonic mixing angle $\theta_{ 13}$ is: $10^{ -2} \lesssim \sin \theta_{ 13} \lesssim 10^{ -1}$, but smaller values are not totally excluded by the model.
Categories: hep-ph