TY  - JOUR
AU  - Aparici, A.
AU  - Herrero-Garcia, J.
AU  - Rius, N.
AU  - Santamaria, A.
PY  - 2012
DA  - 2012//
TI  - On the nature of the fourth generation neutrino and its implications
T2  - J. High Energy Phys.
JO  - Journal of High Energy Physics
SP  - 030
EP  - 31pp
VL  - 07
IS  - 7
PB  - Springer
KW  - Beyond Standard Model
KW  - Neutrino Physics
AB  - 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.
SN  - 1126-6708
UR  - http://arxiv.org/abs/1204.1021
UR  - https://doi.org/10.1007/JHEP07(2012)030
DO  - 10.1007/JHEP07(2012)030
LA  - English
N1  - WOS:000307298400030
ID  - Aparici_etal2012
ER  -