Exploring collider aspects of a neutrinophilic Higgs doublet model in multilepton channels

TL;DR

This paper investigates a neutrinophilic Higgs doublet model with heavy neutrinos, analyzing its collider signatures at the LHC and future colliders, and how neutrino mass hierarchies influence observable phenomena.

Contribution

It introduces a neutrinophilic Higgs model with sizable Yukawa couplings and explores its distinctive collider signals, linking neutrino mass hierarchies to experimental signatures.

Findings

Potential collider signals at LHC and future colliders identified.

Neutrino mass hierarchies influence collider phenomenology.

Enhanced Yukawa couplings lead to observable multilepton events.

Abstract

We consider a neutrinophilic Higgs scenario where the Standard Model is extended by one additional Higgs doublet and three generations of singlet right-handed Majorana neutrinos. Light neutrino masses are generated through mixing with the heavy neutrinos via Type-I seesaw mechanism when the neutrinophilic Higgs gets a vacuum expectation value (VEV). The Dirac neutrino Yukawa coupling in this scenario can be sizable compared to those in the canonical Type-I seesaw mechanism owing to the small neutrinophilic Higgs VEV giving rise to interesting phenomenological consequences. We have explored various signal regions likely to provide a hint of such a scenario at the LHC as well as at future $e^+e^-$ colliders. We have also highlighted the consequences of light neutrino mass hierarchies in collider phenomenology that can complement the findings of neutrino oscillation experiments.