The constraints on the parameters in the decay process ì->e? and ì -> 3e at tree level in the Hung model

摘要

The smallness of neutrino masses is naturally explained by the seesaw mechanism, which is usually implemented by assuming a small Dirac mass of order charged leptons' and a large mass of sterile neutrinos of order GUT scale [1]. This makes heavy neutrinos experimentally inaccessible. If heavy neutrinos have a mass of order electroweak scale, they could be detected at high energy colliders. A model with this feature built in has been suggested recently by Hung. We analyze the constraints on the unknown parameters in the decay ì->e? and ì -> 3e.