Explaining Dark Matter and Neutrino Mass in the light of TYPE-II Seesaw Model

TL;DR

This paper extends the Type-II seesaw model with an additional scalar doublet to simultaneously explain dark matter stability and neutrino masses, deriving stability conditions and exploring phenomenological implications including collider signatures.

Contribution

It introduces a novel extended Type-II seesaw model with a stable dark matter candidate and derives comprehensive stability and unitarity conditions for the first time.

Findings

Stable dark matter candidate identified within the model.

Derived full vacuum stability and unitarity conditions.

Explored collider signatures at 13 TeV LHC.

Abstract

With the motivation of simultaneously explaining dark matter and neutrino masses, mixing angles, we have invoked the Type-II seesaw model extended by an extra $SU(2)$ doublet $\Phi$. Moreover, we have imposed a $\mathbb{Z}_2$ parity on $\Phi$ which remains unbroken as the vacuum expectation value of $\Phi$ is zero. Consequently, the lightest neutral component of $\Phi$ becomes naturally stable and can be a viable dark matter candidate. On the other hand, light Majorana masses for neutrinos have been generated following usual Type-II seesaw mechanism. Further in this framework, for the first time, we have derived the full set of vacuum stability and unitarity conditions, which must be satisfied to obtain a stable vacuum as well as to preserve the unitarity of the model respectively. Thereafter, we have performed extensive phenomenological studies of both dark matter and neutrino sectors considering all possible theoretical and current experimental constraints. Finally, we have also discussed a qualitative collider signatures of dark matter and associated odd particles at the 13 TeV Large Hadron Collider.