TY  - JOUR
AU  - Cepedello, R.
AU  - Fonseca, R. M.
AU  - Hirsch, M.
PY  - 2018
DA  - 2018//
TI  - Systematic classification of three-loop realizations of the Weinberg operator
T2  - J. High Energy Phys.
JO  - Journal of High Energy Physics
SP  - 197
EP  - 34pp
VL  - 10
IS  - 10
PB  - Springer
KW  - Beyond Standard Model
KW  - Neutrino Physics
AB  - We study systematically the decomposition of the Weinberg operator at three-loop order. There are more than four thousand connected topologies. However, the vast majority of these are infinite corrections to lower order neutrino mass diagrams and only a very small percentage yields models for which the three-loop diagrams are the leading order contribution to the neutrino mass matrix. We identify 73 topologies that can lead to genuine three-loop models with fermions and scalars, i.e. models for which lower order diagrams are automatically absent without the need to invoke additional symmetries. The 73 genuine topologies can be divided into two sub-classes: normal genuine ones (44 cases) and special genuine topologies (29 cases). The latter are a special class of topologies, which can lead to genuine diagrams only for very specific choices of fields. The genuine topologies generate 374 diagrams in the weak basis, which can be reduced to only 30 distinct diagrams in the mass eigenstate basis. We also discuss how all the mass eigenstate diagrams can be described in terms of only five master integrals. We present some concrete models and for two of them we give numerical estimates for the typical size of neutrino masses they generate. Our results can be readily applied to construct other d = 5 neutrino mass models with three loops.
SN  - 1029-8479
UR  - http://arxiv.org/abs/1807.00629
UR  - https://doi.org/10.1007/JHEP10(2018)197
DO  - 10.1007/JHEP10(2018)197
LA  - English
N1  - WOS:000449260800013
ID  - Cepedello_etal2018
ER  -