Use of Compton suppression gamma ray spectrometry to determine 239Pu

C Egozi; S Landsberger; W S Charlton; S E Betts; R Winkler

doi:10.1016/j.apradiso.2023.110717

Use of Compton suppression gamma ray spectrometry to determine ²³⁹Pu

Appl Radiat Isot. 2023 Apr:194:110717. doi: 10.1016/j.apradiso.2023.110717. Epub 2023 Feb 8.

Authors

C Egozi¹, S Landsberger², W S Charlton³, S E Betts¹, R Winkler¹

Affiliations

¹ Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM, 87545, USA.
² Nuclear Engineering Teaching Lab, University of Texas at Austin, Pickle Research Campus, R-9000, Austin, TX, 78712, USA. Electronic address: s.landsberger@mail.utexas.edu.
³ Nuclear Engineering Teaching Lab, University of Texas at Austin, Pickle Research Campus, R-9000, Austin, TX, 78712, USA.

PMID: 36774821
DOI: 10.1016/j.apradiso.2023.110717

Abstract

²³⁹Pu has been characterized by gamma-ray spectroscopy for a level higher than the usual environmental ones typically needing alpha spectrometry, ICP-MS or TIMS. The higher activities typically have applications in reprocessing, safeguards verification, and nuclear forensics. For activities of hundreds of Bq/g, it is possible to use gamma ray spectrometry for ²³⁹Pu characterization. A soil reference standard of 185 Bq/g (75 ng/g) was measured on a 79% efficient HPGe with a digital Compton suppression system. The ratios of the counting statistics for suppressed and unsuppressed uncertainties for various ²³⁹Pu photopeaks were determined. The effects of self-attenuation on the low energy gamma rays were evaluated, and it was determined that Compton suppression was an effective characterization method of ²³⁹Pu after accounting for self-attenuation.

Keywords: (239)Pu; Compton suppression; Gamma ray self-attenuation.