SCINTILLATOR SPENT FUEL MONITOR

Year
1980
Author(s)
W. Bernard - Los Alamos National Laboratory
C.E. Moss - Los Alamos Scientific Laboratory
Abstract
A monitor for rapidly measuring the gross gamma-ray flux immediately above spent fuel assemblies in underwater storage racks has been developed. It consists of a plastic scintillator, photomultiplier, collimator, and a small battery-powered electronics package. The crosstalk from an isolated fuel assembly to an adjacent void is only about 2%. The mean difference between the measured gamma-ray flux and the flux estimated from the declared burnup and cooling time with a simple formula is 22%.