  Various groups have demonstrated that antineutrino monitoring can be
successful in assessing the plutonium content in water-cooled nuclear reactors
for nonproliferation applications. New reactor designs and concepts incorporate
nontraditional fuels types and chemistry. Understanding how these properties
affect the antineutrino emission from a reactor can extend the applicability of
antineutrino monitoring. Thorium molten salt reactors (MSR) breed U-233, that
if diverted constitute a direct use material as defined by the International
Atomic Energy Agency (IAEA). The antineutrino spectrum from the fission of
U-233 has been estimated for the first time, and the feasibility of detecting
the diversion of 8 kg of U-233, within a 30 day timeliness goal has been
evaluated. The antineutrino emission from a thorium reactor operating under
normal conditions is compared to a diversion scenario by evaluating the daily
antineutrino count rate and the energy spectrum of the detected antineutrinos
at a 25 meter standoff. It was found that the diversion of a significant
quantity of U-233 could not be detected within the current IAEA timeliness
detection goal using either tests. A rate-time based analysis exceeded the
timeliness goal by 23 days, while a spectral based analysis exceeds this goal
by 31 days.
