Diffractive photoproduction of dijets at ZEUS

Abstract

The diffractive photoproduction of dijets has been studied using 77.6 pb −1 of data taken by the ZEUS detector at HERA. The measurements have been made in the kinematic range 0.2< y <0.85 and x IP < 0.035 , where y is the inelasticity and x IP is the fraction of the proton momentum taken by the diffractive exchange. The jets are reconstructed using the k T algorithm. The two highest transverse energy jets are required to satisfy E T > 7.5 and 6.5 GeV, respectively, and to lie in the pseudorapidity range −1.5< η <2.0. Differential cross sections have been measured and are confronted with the predictions from leading order Monte Carlo models and next-to-leading order QCD calculations.