MINIMIZING ENVIRONMENTAL IMPACTS ON THE ACCURACY OF A URANIUM ENRICHMENT MONITOR BASED ON A NaI(Tl) SPECTROMETER AND A TRANSMISSION SOURCE

Year
2007
Author(s)
Donald A. Close - Los Alamos National Laboratory
Tom Hill - Los Alamos National Laboratory
Calvin E. Moss - Los Alamos National Laboratory
K. D. Ianakiev - Los Alamos National Laboratory
T. Marks - Los Alamos National Laboratory
B S Alexandrov - Los Alamos National Laboratory
Dale Murray - Sandia National Laboratories
D. A. Dale - Los Alamos National Laboratory
H. Nguyen - Los Alamos National Laboratory
Abstract
Enrichment monitors that are based on a NaI(Tl) spectrometer and a transmission source are very sensitive to errors in the intensity of the transmission peak. The effect of environmental factors as temperature and pickup noise on enrichment accuracy has been evaluated. By using a patented technology in place of a traditional NaI(Tl) detector preamplifier, we were able to reduce temperature errors by an order of magnitude, thereby improving the count-rate characteristics of the NaI(Tl) spectrometer. A simple method for diagnosing the noise immunity of installed instrumentation as well as our experience in reducing noise sensitivity in harsh industrial environments will be presented.