SuperCDMS SNOLAB: Calibration, Commissioning, and Beyond

多项天文观测已经确定，宇宙中大约85%的物质不是由正常原子组成的，而是不发射或吸收光的未被检测到的基本“暗物质”粒子。破译这种所谓的暗物质的性质对宇宙学、天体物理学和高能粒子物理学具有根本的重要性。一个主要的假设是，它是由弱相互作用大质量粒子（WIMP）组成的，这些粒子是在大爆炸后产生的。如果WIMP是暗物质，那么它们在我们星系中的存在可能是通过位于地下深处的探测器中的原子核散射来检测的，以帮助排除宇宙射线造成的背景。对WIMP暗物质的直接探测将解决粒子物理学和宇宙学中的一个基本谜团，为了解宇宙的主要物质组成和粒子物理学标准模型之外的物理学提供了一个独特的窗口。该奖项将支持在SuperCDMS SNOLAB实验中工作的学生和科学家，该实验旨在实现1-10 GeV/c2质量范围内的暗物质搜索的世界领先灵敏度。SuperCDMS SNOLAB实验将产生广泛的影响，超出对暗物质的搜索。实验和研发工作进一步推进了声子介导的探测器和新的主动否决概念，这些概念可以在宇宙学，天文学和工业中应用。这一努力将有助于本科生和研究生和博士后研究人员的培训，继续小组？通过参加夏季研究机会计划（SROP），该计划将来自美国各地的本科生带到西北大学进行夏季研究，从而大力参与指导来自代表性不足群体的本科生。该奖项有以下目标：（1）通过分析现有SuperCDMS Soudan数据中的电子反冲暗物质候选物，测量暗物质信号或在质量低于10 GeV/c2的WIMP-核子截面方面设定世界领先的极限;（2）在SNOLAB的CUTE测试设施中测试第一批生产SuperCDMS SNOLAB探测器的性能;（3）在SuperCDMS SNOLAB实验的预操作和调试中发挥核心作用。该奖项将重点关注核能刻度的校准，这是一种对从SuperCDMS SNOLAB获得科学至关重要的测量。核能规模将在一个专门的测试活动中进行测量，使用三角大学核实验室（TUNL）中子束设施的小型R D探测器进行高分辨率电离产额测量，并在费米实验室的新NEXUS（西北实验地下站点）使用全尺寸SuperCDMS SNOLAB探测器。

Multiple astronomical observations have established that about 85% of the matter in the universe is not made of normal atoms, but must be otherwise undetected elementary "dark matter" particles that do not emit or absorb light. Deciphering the nature of this so-called Dark Matter is of fundamental importance to cosmology, astrophysics, and high-energy particle physics. A leading hypothesis is that it is comprised of Weakly Interacting Massive Particles, or WIMPs, that were produced moments after the Big Bang. If WIMPs are the dark matter, then their presence in our galaxy may be detectable via scattering from atomic nuclei in detectors located deep underground to help reject backgrounds due to cosmic rays. Direct detection of WIMP dark matter would solve a fundamental mystery in particle physics and cosmology, providing a unique window to learning about the primary matter constituent of the Universe and of physics beyond the Standard Model of particle physics. This award will support students and scientists working on the SuperCDMS SNOLAB experiment that aims to achieve world-leading sensitivity for dark matter searches in the 1-10 GeV/c2 mass range.The SuperCDMS SNOLAB experiment will have a broad impact which extends beyond the search for dark matter. The experimental and R&D efforts further advance phonon-mediated detectors and new active veto concepts, which can have applications in cosmology, astronomy and industry. This effort will contribute to the training of undergraduate and graduate students and postdoctoral researchers, continuing the group?s strong involvement in mentoring undergraduates from underrepresented groups by participating in the Summer Research Opportunities Program (SROP), which brings undergraduates from across the U.S. to do a summer of research at Northwestern. This award has the following objectives: (1) to measure a dark matter signal or place world-leading limits for the WIMP-nucleon cross section at masses below 10 GeV/c2 by analyzing the electron-recoiling dark matter candidates from the existing SuperCDMS Soudan data; (2) to performance test the first production SuperCDMS SNOLAB detectors at the CUTE test facility in SNOLAB; and (3) to play a central role in the pre-operations and commissioning of the SuperCDMS SNOLAB experiment. This award will focus on the calibration of the nuclear energy scale, which is a measurement which is essential to obtain science from SuperCDMS SNOLAB. The nuclear energy scale will be measured in a dedicated testing campaign using both high resolution ionization yield measurements using small R&D detectors at the Triangle Universities Nuclear Laboratory (TUNL) neutron beam facility, and full-size SuperCDMS SNOLAB detectors at the new NEXUS (Northwestern Experimental Underground Site) at Fermilab.