Explanation for the low flux of high-energy astrophysical muon neutrinos.

There has been some concern about the unexpected paucity of cosmic high-energy muon neutrinos in detectors probing the energy region beyond 1 PeV. As a possible solution we consider the possibility that some exotic neutrino property is responsible for reducing the muon neutrino flux at high energies from distant sources; specifically, we consider (i) neutrino decay and (ii) neutrinos being pseudo-Dirac-particles. This would provide a mechanism for the reduction of high-energy muon events in the IceCube detector, for example.

Predictive flavor symmetries of the neutrino mass matrix.

Here we propose an A(4) flavor symmetry model that implies a lower bound on the neutrinoless double beta decay rate, corresponding to an effective mass parameter M{ee} > or similar to 0.03 eV, and a direct correlation between the expected magnitude of CP violation in neutrino oscillations and the value of sin{2}theta{13}, as well as a nearly maximal CP phase delta.