LUX Operations at the Sanford Underground Research Facility

观测表明，宇宙中80%的物质不是由正常原子组成的，而是不发射或吸收光线的、未被探测到的基本“暗物质”粒子。值得注意的是，出于其他原因提出的粒子物理理论预测，存在具有合适性质的弱相互作用大质量粒子(WIMP)，正是这种暗物质。如果WIMP是暗物质，那么当它们在地球上的探测器中散射时，它们可能是可以探测到的。直接探测WIMP暗物质将解开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超越粒子物理标准模型的物理学提供了一个独特的窗口。大型地下氙气实验(LUX)是一种两相(液/气)氙气(LXE)实验，旨在探索暗物质与普通物质的相互作用。与LXE相关的技术的发展将在世界范围内越来越多的使用稀有液体作为探测材料的实验中找到用处。这些项目还将为研究生和本科生提供辐射探测、低温和气体净化方面的技术培训。LXE在天体物理、国土安全和医学成像的伽马射线成像方面有实际应用。LUX经常参观该设施，并为该地区的学校和大学课堂介绍地下实验，他们与该地区的美洲印第安人学院和部落议会保持着强有力的联系。LUX位于南达科他州铅的桑福德地下研究设施(SURF)，其基准质量约为100公斤，有望显著提高对WIMP模型的敏感度。到目前为止，LUX拥有世界上对6GeV以上WIMP质量的与自旋无关的暗物质相互作用最敏感的极限。这项奖励为2015年3月至2016年12月期间LUX的继续运营和随后的退役提供支持。预计到2016年年中，LUX的持续运行将导致敏感度显著提高，在高WIMP质量时，比现有限制提高5倍。

Observations indicate that 80% 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. Remarkably, particle physics theories proposed for other reasons predict the existence of Weakly Interacting Massive Particles (WIMPs) with just the right properties to be this dark matter. If WIMPs are the dark matter, they may be detectable when they scatter in Earth-based detectors. 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. The Large Underground Xenon experiment (LUX) is a two-phase (liquid/gas) xenon (LXe) experiment designed for the search for dark matter interactions with ordinary matter.Development of technology related to LXe will find use in the increasing number of experiments worldwide using noble liquids as detection materials. These projects will also result in technical training in radiation detection, cryogenics, and gas purification for graduate and undergraduate students. LXe has practical applications to gamma ray imaging for astrophysics, Homeland Security, and medical imaging. There are frequent tours of the facility and presentations on the underground experiments for the region's schools and college classes, and they maintain strong outreach efforts to the region's American Indian Colleges and Tribal Councils.Located in the Sanford Underground Research Facility (SURF) in Lead, South Dakota, LUX has a fiducial mass of about 100 kg and promises substantially improved sensitivity to the WIMP model. From its operations to date, LUX has the most sensitive limit in the world for spin-independent dark matter interactions for WIMP masses above 6 GeV. This award provides support for continued LUX operations, followed by decommissioning, over the period of March 2015 through December 2016. Continued LUX operation through mid-2016 is expected to result in considerably improved sensitivity, reaching a factor of five in improvement over existing limits at high WIMP masses.