Singlet-Doublet Fermionic Dark Matter, Neutrino Mass and Collider Signatures

Understand

We propose a minimal extension of the standard model (SM) by including a scalar triplet with hypercharge 2 and two vector-like leptons: one doublet and a singlet, to explain simulatenously the non-zero neutrino mass and dark matter (DM) content of the Universe.

• The DM emerges out as a mixture of the neutral component of vector-like lepton doublet and singlet, being odd under a discrete $Z_2$ symmetry.
• After electroweak symmetry breaking the triplet scalar gets an induced vev, which give Majorana masses not only to the light neutrinos but also to the DM.
• Due to the Majorana mass of DM, the $Z$ mediated elastic scattering with nucleon is forbidden.