Twist-4 Distribution Amplitudes of the K${}^{\ast }$ and $\varphi$ Mesons in QCD

We present a systematic study of twist-4 light-cone distribution amplitudes of the $K^{\ast }$ and $\varphi$ meson in QCD. The structure of SU(3)-breaking corrections is studied in detail. Non-perturbative input parameters are estimated from QCD sum rules and a renormalon based model. As a by-product, we give a complete reanalysis of the parameters of the twist-4 $\rho$-meson distribution amplitudes.