论文标题
由于表面无线电障碍而引起的katrin背景
KATRIN background due to surface radioimpurities
论文作者
论文摘要
Karlsruhe Tritrium Neutrino（Katrin）实验的目标是确定有效的电子抗神经质量，灵敏度为0.2 ev/c $^2 $ 90％C.L.只能以每秒0.01计数的订单为0.01的背景水平才能实现此目标。可能的背景源是Katrin主光谱仪内表面上的$α$订单。两个$α$ -Sources，$^{223} $ ra和$^{228} $ th安装在Katrin主光谱仪上，目的是临时增加背景，以研究$α$ - $ -DECECAY诱导的背景过程。在本文中，我们介绍了这两个放射性来源进行的背景生成机制和测量。我们的结果表明，内部光谱仪表面上的$α$活性与光谱仪体积的背景之间存在明显的相关性。主光谱仪背景的两个关键特征 - 对内电极偏移势的依赖性以及径向分布 - 可以通过人工诱导的背景再现。这些发现表明，$α$ -DECAY引起的事件对残留的Katrin背景有很高的贡献。
The goal of the KArlsruhe TRItrium Neutrino (KATRIN) experiment is the determination of the effective electron antineutrino mass with a sensitivity of 0.2 eV/c$^2$ at 90% C.L. This goal can only be achieved with a very low background level in the order of 0.01 counts per second. A possible background source is $α$-decays on the inner surface of the KATRIN Main Spectrometer. Two $α$-sources, $^{223}$Ra and $^{228}$Th, were installed at the KATRIN Main Spectrometer with the purpose of temporarily increasing the background in order to study $α$-decay induced background processes. In this paper, we present a possible background generation mechanism and measurements performed with these two radioactive sources. Our results show a clear correlation between $α$-activity on the inner spectrometer surface and background from the volume of the spectrometer. Two key characteristics of the Main Spectrometer background -the dependency on the inner electrode offset potential, and the radial distribution - could be reproduced with this artificially induced background. These findings indicate a high contribution of $α$-decay induced events to the residual KATRIN background.
