Analysis of the Antineutrino Signature of LEU/MOX Fueled LWRs

Thomas Saller, University of Michigan

Antineutrinos are produced in nuclear reactors by the beta decay of fission products. Because of their low interaction probability, most of the antineutrinos produced in a reactor will escape. They can then be detected through another low-probability event, inverse beta decay, in detectors located outside of the reactor. Differences in antineutrino production from a nuclear reactor can be used to determine whether the reactor is loaded with low-enriched uranium (LEU) or mixed-oxide (MOX) fuel and to discriminate between weapons-grade and reactor-grade MOX fuel. The differences between fuel types occur because fission product yields, and therefore antineutrino production rates, are isotope dependent. An analysis of the time-dependent antineutrino production rates for MOX and mixed LEU/MOX cores is done with the HELIOS/PARCS code package. The results of parametric studies performed on these cores are presented and situations in which the diversion of weapons-grade MOX is detectable are identified. Parametric studies include the replacement of one or more weapons-grade MOX assemblies from the core and atypical fuel shuffling.

Abstract Author(s): Thomas Saller, Andrew M. Ward, Tom Downar, David Reyna, Scott Kiff