Neutrino Mass Patterns within the See-saw Model from Multi-localization along Extra Dimensions

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 $\sim {10}^{12}\mathrm{G}\mathrm{e}\mathrm{V}$). The model also predicts Majorana masses between $\sim {10}^{-2}\mathrm{e}\mathrm{V}$ 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.