High Scale Type-II Seesaw, Dominant Double Beta Decay within Cosmological Bound and LFV Decays in SU(5)
Prediction of double beta decay half-life as a function of sterile neutrino mass GeV (blue shaded curve) where the NH type light neutrino and the sterile neutrino exchange contributions have been included. Effects of much larger masses have been neglected. The spread in the curve reflects uncertainty in the virtuality momentum MeV. For comparison, the standard prediction with NH and IH pattern of light neutrino mass hierarchies is shown by the two respective horizontal lines. The bottom most thick red horizontal line closest to the X-axis represents overlapping experimental bounds from different groups [78–82].