The absolute γ-ray branching ratios (emission probabilities) for 19 prominent peaks in the α decay of 233U are reported with energies ranging from 97 to 366 keV. The branching ratios were obtained from α-γ coincidence measurements, normalized to the α singles. The high-purity 233U material (>99.98%) was separated from its decay products before preparation of a 4.74-mg/cm2 uranyl nitrate foil with a 6-mm diameter. This is the first report on the absolute normalization of the branching ratios since 1984 and it is the only measure by α-γ coincidences, where the α-γ/α ratio removes several potential systematic biases. Overall, the results are consistent with the adopted literature and they validate the quantities most relevant to the non-destructive assay of fissile 233U material, which is relevant to the thorium fuel cycle and associated safeguards.

中文翻译：

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233U 衰变后突出γ α射线的绝对分支比


报告了 233U α衰变中 19 个突出峰的绝对γ射线支化比（发射概率），能量范围为 97 至 366 keV。分支比率是从 α-γ 重合测量中获得的，归一化为 α 个单。在制备直径为 6 mm 的 4.74 mg/cm2 硝酸铀酰箔之前，将高纯度 233U 材料 （>99.98%） 与其衰变产物分离。这是自 1984 年以来关于分支比率绝对归一化的第一份报告，也是唯一一个通过 α-γ 巧合来衡量的报告，其中 α-γ/α 比率消除了几个潜在的系统偏差。总体而言，结果与采用的文献一致，并且它们验证了与裂变 233U 材料的无损分析最相关的数量，这与钍燃料循环和相关保障措施相关。