Centre National de la Recherche Scientifique et Technologique (DE/IRSAT/CNRST), Ouagadougou, Burkina Faso.
Comprehensive Nuclear Test-Ban Treaty Organization (IDC/CTBTO), Vienna, Austria.
J Environ Radioact. 2019 Nov;208-209:106014. doi: 10.1016/j.jenvrad.2019.106014. Epub 2019 Jul 16.
This work focuses on the usability of event zero time determination using xenon isotopic activity ratios. Two data sets from Nevada underground nuclear test and Fukushima accident debris were used to calculate the age of radioxenon release by considering three kinds of radioactivity release radionuclide sources: nuclear explosion scenarios, nuclear power reactor release and medical isotopes production facilities release. Typical nuclear power reactor releases were characterized and reference values are proposed for six isotopic activity ratios, which data can be considered as reference point of nuclear reactor effluents at the time of their release obtained from real observations. The same reference values of isotopic activity ratio are given for medical isotopes production facilities releases. The purpose of this study is to evaluate the use of zero-time calculation for source characterization under the assumption that a hypothesis about the event time is made. The event time information may come from a seismo-acoustic event of interest or an inverse atmospheric transport simulation or other context information. For both data sets used in this study, the age precisions are calculated and the time precision difference is evaluated and used as a parameter for the characterization of each radionuclide event. Almost all radioxenon isotopic activity ratios are found to correctly identifying the source type of the radionuclide events studied in this work. The results from this radionuclide events characterization study may be helpful for event screening activities of the Comprehensive Nuclear Test Ban Treaty Organization (CTBTO).
这项工作专注于使用氙同位素活度比来确定事件零时间的可用性。利用来自内华达州地下核试验和福岛事故残骸的两个数据集，通过考虑三种放射性释放放射性核素源：核爆炸情景、核动力反应堆释放和医用同位素生产设施释放，计算了放射性氙释放的年龄。对典型的核动力反应堆释放进行了特征描述，并提出了六个同位素活度比的参考值，这些数据可被视为从实际观测中获得的核反应堆排放物释放时的参考点。医用同位素生产设施释放也给出了相同的同位素活度比参考值。本研究的目的是评估在假设事件时间的假设下，利用零时计算进行源特征描述的用途。事件时间信息可能来自感兴趣的地震-声学事件、反向大气传输模拟或其他上下文信息。对于本研究中使用的两个数据集，计算了年龄精度，并评估了时间精度差异，并将其用作每个放射性核素事件特征描述的参数。几乎所有放射性氙同位素活度比都被发现能够正确识别本工作研究的放射性核素事件的源类型。这项放射性核素事件特征描述研究的结果可能有助于全面禁止核试验条约组织（CTBTO）的事件筛选活动。
