J. Eigenbrodt, W.S. Charlton, A. Solodov, “Sensitivity of Spent Nuclear Fuel Gamma-Ray Measurements”, Proceedings of the INMM 52nd Annual Meeting, Palm Desert, CA, July 17-21, 2011.
While gamma measurements are a well understood technique for estimating burn up and cooling time in spent nuclear fuel, only a few isotopes are currently used and calculations are dependent on operator declarations. Utilizing a larger set of nuclide measurements as well as including low energy measurements (around 100 keV) could provide a significant increase in the information gained from such measurements. Nuclides investigated in this work include Cs-134, Cs-137, Eu-154, Eu-155, Ce-144, Sb-125, Rh-106, Am-241, and x-ray peaks from uranium and plutonium. Low energy, broad range, and high energy gamma measurements have been performed on a variety of spent fuel from PWR and MOX reactors. Selected measured fuel locations have been simulated with Origen, TransLAT, SCALE, and Monteburns to benchmark each of these programs with destructive analysis results. The program which best predicted the measurements was then used to perform a sensitivity analysis of the effects of fuel parameters (burnup, cooling time, and initial enrichment) on each nuclide measurement.