Experimental study of relativistic effects in the dp breakup reaction using the WASA detector

An experiment to investigate the 1 H( ~ d; pp)n breakup reaction at 340 MeV, 360 MeV and 400 MeV deuteron beam energy has been performed at the Cooler Syn- chrotron COSY-Julich with the WASA detector. The main goal was to study of various aspects of few-nucleon dynamics in the medium energy region, with a particular empha- sis on relativistic e ects and their interplay with three nucelon forces. The almost 4 geometry of the WASA detector gives an unique possibility to study the di erent aspects of nucleon-nucleon dynamics in the three nucleon system. The preliminary analysis of the collected data is presented.