A Germanium Detector with Optimized Compton Veto for High Sensitivity at Low Energy

Friedrich, S

Lawrence Livermore National Laboratory

关键词: Plutonium-Gamma;    Radiations;    38 Radiation Chemistry, Radiochemistry, And Nuclear Chemistry;    Fission Products;    Sensitivity;   

DOI  :  10.2172/1033733
RP-ID  :  LLNL-TR-518852
RP-ID  :  W-7405-ENG-48
RP-ID  :  1033733

美国|英语

来源: UNT Digital Library

【 摘 要 】

We have built a prototype germanium detector with a Compton veto that is optimized for high sensitivity in the low-energy range around {approx}100 keV. It is specifically designed to address the problem to directly detect plutonium gamma emissions in spent nuclear fuel by non-destructive assay. This is not possible with current detectors due to the large low-energy background of Compton-scattered high-energy radiation from the fission products, whose gamma flux is at least 6 to 7 orders of magnitude higher than the Pu signal. Our instrument is designed to assess the feasibility to selectively suppress the background in the low-energy region around {approx}100 keV with the strongest Pu X-ray and gamma emissions lines. It employs a thin Ge detector with a large Compton veto directly behind it to suppress the background from forward-scattered radiation by anti-coincidence vetoing. This report summarizes the design considerations and the performance of the instrument.