Measurement of Dijet Production in Diffractive Deep-Inelastic Scattering at HERA

The production of dijets is measured in diffractive deep-inelastic scattering at HERA. The data were recorded with the H1 detector at DESY in the years 2003-2007. Diffractive events are selected by requiring a gap in the rapidity distribution of the hadronic systen, where no particles are produced. Two jets are selected with transverse momenta in the hadronic-centre-of-mass system larger than 4 and 5.5GeV, respectively. Cross sections are measured single- and doubledifferentially in various kinematic quantities. The data are found to be in good agreement with NLO QCD calculations based on diffractive parton densities determined frominclusive diffractive cross section measurements.