ν-two Higgs doublet model and its collider phenomenology

Abstract

Smallness of neutrino masses can be explained by introducing a tiny vacuum expectation value of an extra-Higgs doublet which couples to right-handed neutrinos (N R ). This situation is naturally realized in ν-Two Higgs Doublet Model (νTHDM), where a TeV-scale seesaw mechanism can work well. We investigate observable phenomenology of νTHDM at LHC and ILC experiments. Charged Higgs boson (H ±) in νTHDM is almost originated from the extra-Higgs doublet and its coupling strength to neutrinos are not small. Then this model induces rich phenomenology at the LHC, for example, when m H± < M N observable charged tracks can be induced from long lived charged Higgs. On the other hand, when m H± > M N , right-handed neutrinos can be long-lived, and secondary vertices may be tagged at the LHC. The νTHDM also predicts observable lepton number violating process at the ILC.