Diffractive Dijet and 3-Jet Electroproduction at HERA

A new H1 measurement of diffractive dijet and 3-jet production cross sections in diffractive deep inelastic scattering events of the type ep->eXY is presented. The data constrain well the diffractive gluon distribution. At low x-pom, a calculation based on perturbative QCD is in a reasonable agreement with the data.