High Radiopurity Copper ElectroFormation at the Boulby Underground Laboratory

我们不知道宇宙中大约85%的物质--所谓的暗物质--的性质，也不知道物质中难以捉摸的基本粒子--中微子的性质。科学家们正在通过“稀有事件搜索”来揭开这些谜团，即寻找最不寻常的粒子相互作用的实验，例如来自我们银河系的暗物质粒子与实验室中的探测器的相互作用，这种相互作用一年可能只发生几次。为了让稀有事件搜索实验能够成功地观察到这种罕见事件，实验人员非常小心地尽量减少潜在的背景来源，即可能模仿暗物质特征的其他信号。这项工作中最严峻的挑战之一是通过使用极其纯净的材料来抑制探测器部件的天然放射性。由于其令人印象深刻的纯度，超纯电铸铜是材料的选择。英国走在了这一努力的前列。在北约克郡，在地球表面下1.1公里处，博尔比地下实验室是英国的国家深层地下科学设施。博尔比位于英国最深的矿山，拥有举办直接暗物质搜索实验的悠久历史，目前拥有一家最先进的设施，用于评估实验中使用的材料。伯明翰大学在NEWS-G直接暗物质搜索实验的探测器电铸方面处于领先地位，并计划在博尔比安装世界领先的电铸设施。这将用于建造探测器和其他实验部件，并将增强博尔比作为世界级研究设施的地位。这也增强了英国举办下一代国际罕见事件搜索实验的愿望，该实验有可能导致一项改变世界的发现。

We do not know the nature of approximately 85% of the matter in the Universe - the so-called Dark Matter - nor do we understand the nature of the elusive fundamental particles of matter, the neutrinos. Scientists are shining a light on these mysteries using 'rare event searches' - experiments looking for the most extraordinary particle interactions, such as the interaction of Dark Matter particles from our galaxy with a detector in the laboratory, which may only occur a handful of times per year. In order for rare event search experiments to successfully observe such infrequent events, experimenters take great care to minimise potential sources of background, other signals that may mimic the signature of Dark Matter. One of the toughest challenges in this endeavour is to suppress the natural radioactivity of the detector components, by using extremely pure materials. Ultra-pure electroformed copper is the material of choice thanks to its impressive purity. The UK is at the forefront of this endeavour. In North Yorkshire, 1.1 km below the surface of the earth, the Boulby Underground Laboratory is the UK's national deep underground science facility. Situated in the UK's deepest mine, Boulby boasts a long history of hosting direct Dark Matter search experiments and currently hosts a state-of-the-art facility for assessing materials for use in experiments. The University of Birmingham has a leading role in the electroforming of detectors for the NEWS-G direct Dark Matter search experiments and aims to install a world-leading electroforming facility in Boulby. This will be used to construct detectors and other components for experiments and will enhance Boulby's status as a world-class research facility. It also strengthens the UK's aspiration to host an international, next-generation rare event search experiment that has the potential to lead to a world-changing discover.