The spectrum of (h)QCD in the Veneziano limit

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In this note we report on the analysis of the zero temperature spectra of glueballs and mesons for holographic QCD in the Veneziano limit. We work within a holographic bottom-up model named V-QCD which takes into account the full backreaction of the flavor degrees of freedom. By studying the fluctuations of this model we compute spectra of mesons and glueballs as a function of x=Nf/Nc. The spectra are discrete and gapped (modulo the pions) in the QCD regime, where x is below the critical value xc at which the conformal transition takes place. The masses uniformly converge to zero in the walking region x -> xc following Miransky scaling. Moreover, all the ratios of masses asymptote to finite constants as x -> xc. Therefore there is no "dilaton" in the spectrum. Finally, we compute the S-parameter, which is found to be of O(1) in the walking regime.