Longitudinal Z-boson pair production via gluon fusion in technicolor models

We study the coupling of two longitudinal Z-bosons to two gluons via technicolor interactions. Noticing a similarity of this process to $2 \gamma \rightarrow 2 \pi^{0}$, we calculate the amplitude in chiral perturbation theory in one-generation technicolor model. At the invariant mass of $Z_{L}Z_{L}$ above the colored pseudo-Goldstone boson threshold, we find the signal in proton collisions at $\sqrt{s} = 14\, TeV$ is stronger than the standard model background by an order of magnitude, and is large enough to be easily observable at LHC. The cross section for $W_{L}^{+}W_{L}^{-}$ pair production is also presented.