High Radiopurity Copper ElectroFormation at the Boulby Underground Laboratory

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.