In color dipole generalized Balitskiĭ-Fadin-Kuraev-Lipatov dynamics, we predict a strikingly different $Q^2$ and energy dependence of the diffraction slope for the diffractive production of ground state $V\left(1S\right)\mathrm{}$ and radially excited $V^{\prime }\mathrm{}\left(2S\right)\mathrm{}$ light vector mesons. The color dipole model predictions for the diffraction slope for $\rho °$ and $\phi °$ production are in a good agreement with the data from the fixed target and collider DESY HERA experiments. We present how a different pattern of anomalous energy and $Q^2$ dependence of the diffraction slope for $V^{\prime }\mathrm{}\left(2S\right)\mathrm{}$ production leads to a different position of the node in the radial wave function. We discuss how to determine this node position from the fixed target and HERA data.

• Received 24 May 2000

DOI:https://doi.org/10.1103/PhysRevD.63.074007