Transient Effects in Fission Investigated with Proton-on-lead Reactions in Complete Kinematic Measurements

Proton-induced fission of 208Pb has been investigated at 370, 500 and 650 A MeV in complete kinematic measurements. The experiment was performed at GSI Darmstadt where the combined use of the inverse kinematics technique with an efficient detection setup allowed to measure for the first time the atomic and mass number of both fission fragments. The performed measurement together with different model calculations allow us to investigate dissipative and transient effects in the fission process and the dependence on temperature and deformation of the dissipation strength β. The use of spallation reactions with lead projectiles favours this study due to its high excitation energy and low angular momentum.