title: A high-efficiency HPGe coincidence system for environmental analysis.
abstract: The Comprehensive Nuclear-Test-Ban Treaty (CTBT) is supported by a network of certified laboratories which must meet certain sensitivity requirements for CTBT relevant radionuclides. At the UK CTBT Radionuclide Laboratory (GBL15), a high-efficiency, dual-detector gamma spectroscopy system has been developed to improve the sensitivity of measurements for treaty compliance, greatly reducing the time required for each sample. Utilising list-mode acquisition, each sample can be counted once, and processed multiple times to further improve sensitivity. For the 8 key radionuclides considered, Minimum Detectable Activities (MDA's) were improved by up to 37% in standard mode (when compared to a typical CTBT detector system), with the acquisition time required to achieve the CTBT sensitivity requirements reduced from 6 days to only 3. When utilising the system in coincidence mode, the MDA for (60) Co in a high-activity source was improved by a factor of 34 when compared to a standard CTBT detector, and a factor of 17 when compared to the dual-detector system operating in standard mode. These MDA improvements will allow the accurate and timely quantification of radionuclides that decay via both singular and cascade γ emission, greatly enhancing the effectiveness of CTBT laboratories.
authors: AWE, Aldermaston, Reading, Berkshire, RG7 4PR, UK; University of Surrey, Guildford, GU2 7XH, UK. Electronic address: rich.britton@awe.co.uk.
authors: R
authors: R
authors: Britton
authors: AWE, Aldermaston, Reading, Berkshire, RG7 4PR, UK.
authors: A V
authors: AV
authors: Davies
authors: University of Surrey, Guildford, GU2 7XH, UK.
authors: J L
authors: JL
authors: Burnett
authors: AWE, Aldermaston, Reading, Berkshire, RG7 4PR, UK.
authors: M J
authors: MJ
authors: Jackson
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D005857:Germanium; D007391:International Cooperation; D011834:Radiation Monitoring / Q000295:instrumentation*; D011868:Radioisotopes / Q000032:analysis*; D013051:Spectrometry, Gamma / Q000295:instrumentation
chemical_list: D000396:Air Pollutants, Radioactive; D011868:Radioisotopes; D005857:Germanium
keywords: CTBT; Coincidence measurements; Gamma spectroscopy; List-mode; MDA