Type-III scotogenic model: Inflation, dark matter, and collider phenomenology

We explore an extension of the type-III scotogenic model through the inclusion of a real scalar singlet, which play the role of the inflaton by virtue of its nonminimal coupling to the Ricci scalar. This scalar field not only drives inflation but also decays into other particles embedded within the type-III scotogenic framework. Within this theoretical structure, both the inert scalar doublet and the fermionic triplet are instrumental in radiatively generating neutrino masses, while also emerging as viable candidates for dark matter component of the Universe. We conduct a detailed analysis of their relic abundance and assess their prospects for direct detection. Additionally, we examine the potential collider signatures associated with this framework, emphasizing avenues for experimental verification in forthcoming high energy physics experiments. Owing to the suppressed production cross section of the fermionic triplet at the LHC, we extend our analysis to the Future Circular Collider in its hadron-hadron mode (FCC-hh). Within this context, we identify the monoleptonic decay channel of the triplet fermion, accompanied by substantial missing transverse energy, as a salient and experimentally distinguishable signature of the model. Furthermore, our study reveals that the leading-order production cross section of low-mass scalar dark matter lies within the prospective sensitivity reach of both leptonic and hadronic collider experiments, thereby offering promising avenues for experimental scrutiny.