Title: Phenomenological analysis of properties of the right-handed Majorana neutrino in the seesaw mechanism
Abstract: As an extension of our previous work in the seesaw mechanism, we analyze the influence of nonzero ${U}_{e3}$ on the properties (masses and mixing) of the right-handed Majorana neutrinos in three flavors. The quasidegenerate light neutrinos case is also considered. Assuming the hierarchical Dirac neutrino masses, we find the heavy Majorana neutrino mass spectrum is either hierarchical or partially degenerate if ${\ensuremath{\theta}}_{23}^{\ensuremath{\nu}}$ is large. We show that degenerate right-handed (RH) Majorana masses correspond to a maximal RH mixing angle while hierarchical ones correspond to the RH mixing angles which scale linearly with the mass ratios of the Dirac neutrino masses. An interesting analogue to the behavior of the matter-enhanced neutrino conversion and their difference is presented.