Survival probability in diffractive dijet photoproduction

Abstract

We confront the latest H1 and ZEUS data on diffractive dijet photoproduction with next-to-leading order QCD predictions in order to determine whether a rapidity gap survival probability of less than one is supported by the data. We find evidence for this hypothesis when assuming global factorization breaking for both the direct and resolved photon contributions, in which case the survival probability would have to be E_T^jet-dependent, and for the resolved or in addition the related direct initial-state singular contribution only, where it would be independent of E_T^jet.Comment: 8 pages, 7 figures, to appear in the proceedings of the 2008 CERN-DESY workshop on "HERA and the LHC