The Underwater Coincidence Counter (UWCC) For Plutonium Measurements in Mixed Oxide Fuels

Year
1998
Author(s)
M. Abhold - Los Alamos National Laboratory
G. Eccleston - Los Alamos National Laboratory
G. Eccleston - Los Alamos National Laboratory
Michael Baker - Los Alamos National Laboratory
H.O. Menlove - Los Alamos National Laboratory
H.O. Menlove - Los Alamos National Laboratory
Iouri Kulikov - International Atomic Energy Agency
James M. Pecos - Los Alamos National Laboratory
P. DeBaere - EURATOM
Abstract
The use of fresh uranium-plutonium mixed oxide (MOX) fuel in light-water reactors (LWR) is increasing in Europe and Japan and it is necessary to verify the plutonium content in the fuel for international safeguards purposes. The UWCC is a new instrument that has been designed to operate underwater and nondestructively measure the plutonium in unirradiated MOX fuel assemblies. The UWCC can be quickly configured to measure either boiling-water reactor (BWR) or pressurized- water reactor (PWR) fuel assemblies. The plutonium loading per unit length is measured using the UWCC to precisions of less than 1 per cent in a measurement time of 2 to 3 minutes. Initial calibrations of the UWCC were completed on measurements of MOX fuel in Mol, Belgium. The MCNP-REN Monte Carlo simulation code is being benchmarked to the calibration measurements to allow accurate simulations for extended calibrations of the UWCC.