论文标题
$^{222} $ rn发射测量值
$^{222}$Rn emanation measurements for the XENON1T experiment
论文作者
论文摘要
对于低能量稀有事件搜索实验的成功，低放射活性建筑材料的选择至关重要。除了散装中的放射性污染物外，材料表面的放射性ra原子的散发出来，与努力进一步减少此类实验的背景相关。在这项工作中，我们介绍了针对Xenon1t暗物质实验执行的$^{222} $ rn发射测量。与批量杂质筛查活动一起，结果使我们能够选择$^{222} $ rn活动浓度为10 $μ$ bq/kg的$^{222} $ rn活动材料。 $^{222} $ rn来源的分布的知识使我们能够在实验过程中选择性地消除关键组件。将来自发射测量的预测与Xenon1t中的$^{222} $ rn活性浓度的数据进行了比较。最终的$^{222} $ rn活动浓度为（4.5 $ \ pm $ 0.1）$ $ $ $ $ bq/kg Xenon1t的目标是Xenon暗物质实验中有史以来最低的。
The selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the $^{222}$Rn emanation measurements performed for the XENON1T dark matter experiment. Together with the bulk impurity screening campaign, the results enabled us to select the radio-purest construction materials, targeting a $^{222}$Rn activity concentration of 10 $μ$Bq/kg in 3.2 t of xenon. The knowledge of the distribution of the $^{222}$Rn sources allowed us to selectively eliminate critical components in the course of the experiment. The predictions from the emanation measurements were compared to data of the $^{222}$Rn activity concentration in XENON1T. The final $^{222}$Rn activity concentration of (4.5 $\pm$ 0.1) $μ$Bq/kg in the target of XENON1T is the lowest ever achieved in a xenon dark matter experiment.
