VERA, the Vienna Environmental Research Accelerator, is especially equipped for the measurement of actinides, and performs a growing number of measurements on environmental samples. While AMS is not the optimum method for each particular plutonium isotope, the possibility to measure 239Pu, 240Pu, 241Pu, 242Pu and 244Pu on the same AMS sputter target is a great simplification. We have obtained a first result on the global fallout value of 244Pu/239Pu = (5.7 ± 1.0) × 10-5 based on soil samples from Salzburg prefecture, Austria. Furthermore, we suggest using the 242Pu/240Pu ratio as an estimate of the initial 241Pu/239Pu ratio, which allows dating of the time of irradiation based solely on Pu isotopes. We have checked the validity of this estimate using literature data, simulations, and environmental samples from soil from the Salzburg prefecture (Austria), from the shut down Garigliano Nuclear Power Plant (Sessa Aurunca, Italy) and from the Irish Sea near the Sellafield nuclear facility. The maximum deviation of the estimated dates from the expected ages is 6 years, while relative dating of material from the same source seems to be possible with a precision of less than 2 years. Additional information carried by the minor plutonium isotopes may allow further improvements of the precision of the method.

中文翻译：

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次要钚同位素的 AMS。

VERA 是维也纳环境研究加速器，专门用于测量锕系元素，并且对环境样品进行越来越多的测量。虽然 AMS 不是每种特定钚同位素的最佳方法，但在同一个 AMS 溅射靶上测量 239Pu、240Pu、241Pu、242Pu 和 244Pu 的可能性是极大的简化。我们根据奥地利萨尔茨堡州的土壤样本，获得了全球沉降值 244Pu/239Pu = (5.7 ± 1.0) × 10-5 的第一个结果。此外，我们建议使用 242Pu/240Pu 比率作为初始 241Pu/239Pu 比率的估计值，这允许仅基于 Pu 同位素确定辐照时间的年代。我们已经使用文献数据、模拟、以及来自萨尔茨堡州（奥地利）、关闭的加里利亚诺核电站（意大利塞萨奥伦卡）和爱尔兰海塞拉菲尔德核设施附近土壤的环境样本。估计日期与预期年龄的最大偏差为 6 年，而来自同一来源的材料的相对年代似乎可以达到小于 2 年的精确度。次要钚同位素携带的附加信息可以进一步提高方法的精度。而来自同一来源的材料的相对年代似乎可以达到不到 2 年的精确度。次要钚同位素携带的附加信息可以进一步提高方法的精度。而来自同一来源的材料的相对年代似乎可以达到不到 2 年的精确度。次要钚同位素携带的附加信息可以进一步提高方法的精度。