Leszek Motyka (Jagellonian Univerisity)
We present new results on determination of higher twist contributions in diffractive DIS and compare them to the inclusive DIS case. In both cases the framework for the estimates is provided by the saturation model. We discuss the methods of higher twist extraction from the saturation model and compare the results for DIS and DDIS. We point out a striking difference in higher twist importance between DIS and DDIS: at low Q2 the effects are minor in DIS and they are large in DDIS. Moreover a comparison to HERA data hints on a necessary improvement of higher twist treatment in the saturation model. We present a possible QCD explanation of both findings.