%0 Journal Article
%T On the nature of the fourth generation neutrino and its implications
%A Aparici, A.
%A Herrero-Garcia, J.
%A Rius, N.
%A Santamaria, A.
%J Journal of High Energy Physics
%D 2012
%V 07
%N 7
%I Springer
%@ 1126-6708
%G English
%F Aparici_etal2012
%O WOS:000307298400030
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=1157), last updated on Thu, 11 Oct 2012 11:15:22 +0000
%X We consider the neutrino sector of a Standard Model with four generations. While the three light neutrinos can obtain their masses from a variety of mechanisms with or without new neutral fermions, fourth-generation neutrinos need at least one new relatively light right-handed neutrino. If lepton number is not conserved this neutrino must have a Majorana mass term whose size depends on the underlying mechanism for lepton number violation. Majorana masses for the fourth-generation neutrinos induce relative large two-loop contributions to the light neutrino masses which could be even larger than the cosmological bounds. This sets strong limits on the mass parameters and mixings of the fourth-generation neutrinos.
%K Beyond Standard Model
%K Neutrino Physics
%R 10.1007/JHEP07(2012)030
%U http://arxiv.org/abs/1204.1021
%U https://doi.org/10.1007/JHEP07(2012)030
%P 030-31pp