Are the reactions $\gamma \gamma \to V{V}^{\prime }$ a challenge for the factorized Pomeron at high energies?

Abstract

We would like to point to the strong violation of the putative factorized Pomeron exchange model in the reactions $\gamma \gamma \to V{V}^{\prime }$ in the high-energy region where this model works fairly well in all other cases.

Comments: 4 pages, LaTex, 1 fig. in postscript, minor typos corrected, to be published in Phys. Rev. D 60, 117503 (1999)