Li Qi, Wang ShiLian, Fan Yuanqing, Zhao Yungang, Jia Huaimao, Zhang Xinjun, Zhang Ruiqin
CTBT Beijing National Data Centre and Beijing Radionuclide Laboratory, Beijing, 100085, China.
CTBT Beijing National Data Centre and Beijing Radionuclide Laboratory, Beijing, 100085, China.
J Environ Radioact. 2023 Jan;256:107054. doi: 10.1016/j.jenvrad.2022.107054. Epub 2022 Oct 29.
Measurement of the four radioxenon isotopes, namely Xe, Xe, Xe, and Xe, play a key role in underground nuclear test monitoring for ensuring compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). To improve detection sensitivity, a β-γ coincidence technique is commonly used. Due to the presence of the gas matrix, such as stable xenon, nitrogen, helium, the self-attenuation effects should be taken into account when measuring different types of sample. In order to improve the accuracy of the measurement, the detection efficiencies of X-rays and γ-rays were derived by using a simulation gas calibration source with low density of sponge matrix. The detection efficiencies of β-particles and conversion electrons (CEs) were calibrated by measuring radioxenon sample. The self-attenuation correction factors of X-rays and γ-rays were determined by Geant4 simulation method. The self-attenuation correction factors of β-particles and CEs were provided by measuring the radioxenon samples with different volumes of xenon, nitrogen and helium.
对四种放射性氙同位素，即氙-131m、氙-133、氙-133m和氙-135的测量，在地下核试验监测中起着关键作用，以确保符合《全面禁止核试验条约》（CTBT）。为提高检测灵敏度，通常采用β-γ符合技术。由于存在气体基质，如稳定的氙、氮、氦，在测量不同类型样品时应考虑自吸收效应。为提高测量精度，通过使用具有低密度海绵基质的模拟气体校准源得出X射线和γ射线的探测效率。通过测量放射性氙样品校准β粒子和转换电子（CEs）的探测效率。通过Geant4模拟方法确定X射线和γ射线的自吸收校正因子。通过测量含有不同体积氙、氮和氦的放射性氙样品提供β粒子和CEs的自吸收校正因子。
