U and Pu Gamma-Ray Measurements of Spent Fuel Using a Gamma-Ray Mirror Band-Pass Filter

Conference · Wed Jan 01 04:00:00 EST 2014

OSTI ID:1242664

Ziock, Klaus-Peter ^[1]; Alameda, J. B. ^[2]; Brejnholt, N. F. ^[2]; Decker, T. A. ^[2]; Descalle, M. A. ^[2]; Fernandez-Perea, M. ^[2]; Hill, R. M. ^[2]; Kisner, R. A. ^[3]; Melin, A. M. ^[3]; Patton, B. W. ^[2]; Ruz, J. ^[2]; Soufli, R. ^[2]; Pivovaroff, M. J. ^[2]

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1. ORNL
2. Lawrence Livermore National Laboratory (LLNL)
3. Oak Ridge National Laboratory (ORNL)

Abstract. We report on the use of grazing incidence gamma-ray mirrors to serve as a narrow band-pass filter for advanced non-destructive analysis (NDA) of spent nuclear fuel. The purpose of the mirrors is to limit the radiation reaching a HPGe detector to narrow spectral bands around characteristic emission lines from fissile isotopes in the fuel. This overcomes the normal rate issues when performing gamma-ray NDA measurements. In a proof-of-concept experiment, a set of simple flat gamma-ray mirrors were used to directly observe the atomic florescence lines from U and Pu from spent fuel pins with the detector located in a shirt-sleeve environment. The mirrors, consisting of highly polished silicon substrates deposited with WC/SiC multilayer coatings, successfully deflected the lines of interest while the intense primary radiation beam from the fuel was blocked by a lead beam stop. The gamma-ray multilayer coatings that make the mirrors work at the gamma-ray energies used here (~ 100 keV) have been experimentally tested at energies as high as 645 keV, indicating that direct observation of nuclear emission lines from 239Pu should be possible with an appropriately designed optic and shielding configuration.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: NNSA USDOE - National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1242664
• Country of Publication: United States
• Language: English