Systematic Study of One-Loop Dirac Neutrino Masses and Viable Dark Matter Candidates

Understand

We study the generation of small neutrino masses from the dimension six effective operator at tree level and one-loop level, the neutrinos are assumed to be Dirac particles.

• We find out all possible tree and one-loop diagrams which lead to finite neutrino masses.
• The relevant mediator fields and the predictions for neutrino masses are presented.
• The lower order contributions to neutrino masses can be forbidden by introducing soft breaking abelian symmetry or finite non-abelian symmetry.