Diffractive photoproduction of dijets at ZEUS

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 < eta < 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.