Heavy quark signals from radiative corrections to the Z′ boson decay in 3-3-1 models

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One-loop corrections to the Z′ decay width are derived and analyzed in the framework of the general form of the 3-3-1 models. We identify two important sources of corrections: oblique corrections asociated to the Z′ propagator through vacum polarizations induced by virtual particle-antiparticle pairs of new heavy quarks J, and vertex corrections to the Z′qq vertex through virtual exchange of new KQ₁,₂ gauge bosons. Fixing an specific renormalization scheme, we obtain dominant oblique corrections that exhibit a quadratic dependence on the J quark mass, which are absorbed into two oblique parameters: a global parameter ρ′f which modify the Z′ decay width, and a parameter κ′f that define effective Z′ couplings. Numerical results in an specific 3-3-1 model gives a strong contribution of the oblique corrections from about 1.3% in the d(s) quark channel to 10.5% in the neutrino channel, for mⱼ=2 TeV. The vertex corrections contribute to the oblique corrections up to 1.4% for the same channel and mⱼ value. For pp collisions at the CERN LHC collider, we find that the corrections significantly modify the shape of the cross section distributions for e⁺e⁻ and tt final states, where the distributions including the radiative corrections increases up to 1.23 times the tree-level distribution for the dielectron events and to 1.07 for the top events when mⱼ=3 TeV.