MRI: Acquisition of an Ultra-clean, Underground Electroforming and Parts Fabrication Instrumentation Facility

最近在中微子物理学、天体物理学和宇宙学方面的发现彻底改变了我们对中微子、暗物质和宇宙的看法，同时也提出了一系列有趣的相互关联的问题，涉及基本对称性、亚原子粒子的基本相互作用以及中微子在宇宙中扮演的角色。寻找探测这些问题的极其罕见的过程的下一代地下实验需要超清洁材料，包含可获得的最小数量的自然产生的放射性铀(U)和钍(Th)衰减链污染物。这些水平的污染物将在许多计划中的新实验中产生不可接受的背景，例如无中微子双β衰变和暗物质搜索。该合同将提供资金，用于在南达科他州铅的Homestake的Sanford地下实验室的地下安装和运行先进的超清洁电铸仪器。最初的用途将是为Majorana演示器无中微子双β衰变实验生产电铸部件。在这个奖项的更广泛的影响中，仪器和实验室将使未来的实验和整个领域受益。另一个好处是对来自南达科他州和美国的学生、技术人员和科学家进行电铸方法和低本底技术的培训。这些都是重要的学科，是地下科学重要组成部分的基础。

The recent discoveries in neutrino physics, astrophysics, and cosmology have revolutionized our view of neutrinos, dark matter, and the cosmos, while also bringing forth an intriguing set of interconnected questions concerning fundamental symmetries, the basic interactions of subatomic particles, and the role neutrinos play in the universe. Next generation underground experiments searching for the extremely rare processes that probe these questions require ultra-clean materials, containing the smallest obtainable amounts of naturally occurring radioactive uranium (U) and thorium (Th) decay-chain contaminants. Contaminants at these levels will produce unacceptable backgrounds in many of the planned new experiments, such as neutrinoless double beta-decay and dark matter searches. This award will provide funds for advanced, ultra-clean electroforming instrumentation to be installed and operated underground at the Sanford Underground Laboratory at Homestake in Lead, SD. The initial use will be for the production of electroformed components for the Majorana Demonstrator neutrino-less double beta decay experiment. Among the Broader Impacts of this award, the instrumentation and laboratory will benefit future experiments and the field in general. An additional benefit will be the training of students, technicians, and scientists, from both South Dakota and the US, in electroforming methods and low-background techniques. These are important disciplines that serve as a foundation for a substantial component of underground science.