ADS reactivity measurements from MUSE to TRADE (and where do we go from here?)

This paper provides a link between the MUSE (Multiplication avec Source Externe) program performed at CEA-Cadarache in France, and the TRADE (TRIGA Accelerator Driven Experiment) program performed at ENEA-Casaccia in Italy. In both programs, extensive measurements were made to determine the best methods for sub-criticality measurements in an accelerator-driven system. A very serious attempt was made to quantify the uncertainties associated with such measurements. While both MUSE and TRADE studied the methods of sub-criticality determination, in fact the two systems are very different. MUSE was a fast system with MOX fuel (generation time around 0.5 μs), and TRADE was performed in a TRIGA reactor (generation time around 50 μs). This paper will summarize the important results of these two experiments, with the main purpose being to tie them together to attempt to draw generic conclusions that can be applied in the future to a real ADS. In addition, this paper will briefly discuss the next series of experiments that will continue this work in the U.S. (RACE, Reactor Accelerator Coupled Experiments), Belarus (YALINA), Belgium (GUINEVERE), and Russia (SAD, Sub-critical Assembly Dubna). MUSE and TRADE have contributed greatly to our understanding of the uncertainties associated with sub-critical measurements, but there are still some gaps that must be covered. This paper will describe the gaps that exist, and demonstrate how the above future programs will fill in the missing information needed for the design of an actual ADS system in the future. (authors)