Designing an upgrade of the Medley setup for light-ion production and fission cross-section measurements

Expected uncertainties are reported for both types of measurements. The simulations have shown that a simultaneous precision measurement of the three standard cross-sections H(n,n), 235U(n,f) and 238U(n,f) relative to each other is feasible using a triple layered target. As high resolution timing detectors for fission fragments we plan to use Parallel Plate Avalanche Counters (PPACs). The simulation results have put some restrictions on the design of these detectors as well as on the target design. This study suggests a fissile target no thicker than 2μm (1.7 mg/cm2) and a PPAC foil thickness preferably less than 1μm. We also comment on the usability of Geant4 for simulation studies of neutron reactions in this energy range.