A 220Rn source for the calibration of low-background experiments
A 220Rn source for the calibration of low-background experiments
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DOI：
10.1088/1748-0221/11/04/p04004
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发表时间：
2016-04-01
影响因子：
1.3
通讯作者：
Simgen, H.
中科院分区：
文献类型：
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作者：
Lang, R. F.;Brown, A.;Simgen, H.
我们表征两个40 kBq源的电沉积Th-228用于低本底实验。这些源有效地散发Rn-220，一种可以在检测器体积中扩散的惰性气体。Rn-220及其子体同位素产生α-、β-和γ-辐射，其可用于校准各种探测器响应和特征，然后在仅几天内完全衰变。我们进行各种测试，以限制其他长寿命同位素的释放。特别地，我们发现Th-228的放射性小于0.008 atoms/min/kBq（90%CL），Ra-224的放射性为（1.53 +/- 0.04）atoms/min/kBq。这些源特别适用于校准采用液态稀有元素（如氩和氙）的探测器。随着源安装在惰性气体系统中，我们证明了过滤器在进一步降低这些长寿命同位素的活性方面非常有效。因此，我们确认了这些源的适用性，甚至用于下一代实验，如XENON 1 T/XENONnT，LZ和nEXO。
We characterize two 40 kBq sources of electrodeposited Th-228 for use in low-background experiments. The sources efficiently emanate Rn-220, a noble gas that can diffuse in a detector volume. Rn-220 and its daughter isotopes produce alpha-, beta-, and gamma-radiation, which may used to calibrate a variety of detector responses and features, before decaying completely in only a few days. We perform various tests to place limits on the release of other long-lived isotopes. In particular, we find an emanation of < 0.008 atoms/min/kBq (90% CL) for Th-228 and (1.53 +/- 0.04) atoms/min/kBq for Ra-224. The sources lend themselves in particular to the calibration of detectors employing liquid noble elements such as argon and xenon. With the source mounted in a noble gas system, we demonstrate that filters are highly efficient in reducing the activity of these longer-lived isotopes further. We thus confirm the suitability of these sources even for use in next-generation experiments, such as XENON1T/XENONnT, LZ, and nEXO.