Dark matter candidate in an extended type III seesaw scenario

Understand

The type III seesaw mechanism for neutrino mass generation usually makes use of at least two $Y = 0$, $SU(2)_L$ lepton triplets.

• We augment such a model with a third triplet and a sterile neutrino, both of which are odd under a conserved $\Z_2$ symmetry.
• With all new physics confined to the $\Z_2$-odd sector, whose low energy manifestation is in some higher-dimensional operators, a fermionic dark matter candidate is found to emerge.
• We identify the region of the parameter space of the scenario, which is consistent with all constraints from relic density and direct searches, and allows a wide range of masses for the dark matter candidate.