Measurement of the cross-section for the process ee → eeγb7γb7 → eeX at √See = 189 GeV

Abstract The hadronic structure of interactions of virtual photons ( γ b 7 ) is investigated using the reaction ee → ee γ b 7 γ b 7 → eeX based on data taken by the OPAL experiment at √ S ee = 189 GeV, where X represents the hadronic final state. The measured differential cross-sections are compared to the predictions of the leading order Monte Carlo model PHOJET1.10, and to a BFKL calculation. PHOJET1.10 describes the data reasonably well, whereas the cross-section prediction based on a BFKL calculation is significantly too high.