Modified top quark condensation model with the extra heavy fermion, the 125 GeV pseudo-Goldstone boson, and the additional heavy scalar bosons

We discuss the modified top quark condensation model proposed in Ref. 54. This construction was inspired by the top-seesaw scenario, in which the extra heavy fermion χ that may be paired with the top quark is added. Besides, this model incorporates the ideas of the little Higgs scenario, in which the 125 GeV scalar particle appears as a pseudo-Goldstone boson. This model admits (in addition to the 125 GeV scalar boson H) the heavier scalar excitation H′. We consider the region of parameters, where its mass is M_H′ ∼ 1 TeV, the width of H′ is τ_H′ ∼ 0.3M_H′, while the mass of the heavy fermion is m_χ ∼ 1 TeV. We find that in this model the value of the cross-section σ_{pp→H′+X→γ+γ+γ+X} for √s = 13 TeV is essentially smaller than the present experimental upper bound. Besides, we find that for the chosen values of parameters there should exist the CP-even scalar boson with mass ≈ 2m_χ and very small width. In addition, the model predicts the existence of the extra neutral CP-even scalar boson and the charged scalar boson with masses of the order of 1 TeV.