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Considering the classical two-point correlators built from (axial)-vector,scalar \bar qq and gluonium currents, we confront results obtained using theSVZ + 1/q^2 expansion to the ones from some QCD holographic models in theEuclidian region and with negative dilaton \Phi_i(z)=- |c_i^2| z^2. We concludethat the presence of the 1/q^2-term in the SVZ-expansion due to a tachyonicgluon mass appears naturally in the Minimum Soft Wall (MSW) and theGauge/String Dual (GSD) models which can also reproduce semi-quantitativelysome of the higher dimension condensate contributions appearing in the OPE. TheHard-Wall model shows a large departure from the SVZ + 1/q^2 expansion in thevector, scalar and gluonium channels due to the absence of any powercorrections. The equivalence of the MSW and GSD models is manifest in thevector channel through the relation of the dilaton parameter with the tachyonicgluon mass. For approximately reproducing the phenomenological values of thedimension d=4,6 condensates, the holographic models require a tachyonic gluonmass (\alpha_s/\pi)\lambda^2= -(0.12- 0.14) GeV^2, which is about twice thefitted phenomenological value from e^+e^- data. The relation of the inverselength parameter c_i to the tachyonic gluon mass also shows that c_i is channeldependent but not universal for a given holographic model. Using the MSW modeland M_\rho=0.78 GeV as input, we predict a scalar \bar qq mass M_S=(0.95-1.10)GeV and a scalar gluonium mass M_G= (1.1- 1.3) GeV.

SVZ + 1/q2 expansion versus some QCD holographic Models