  We examined the influence of additional scalar doublet on the parameter space
of the Standard Model supplemented with a generation of new vector like
leptons. In particular we identified the viable regions of parameter space by
inspecting various constraints especially electroweak precision (S, T and U)
parameters. We demonstrated that the additional scalar assists in alleviating
the tension of electroweak precision constraints and thus permitting larger
Yukawa mixing and mass splittings among vector like species. We also compared
and contrasted the regions of parameter space pertaining to the latest LHC
Higgs to diphoton channel results in this scenario with vector like leptons in
single Higgs doublet and pure two Higgs doublet model case.

High Energy Physics - Phenomenology