RUI: The DRIFT Directional Search for Dark Matter with Spin-Dependent Couplings

RUI：利用自旋相关耦合对暗物质进行 DRIFT 定向搜索

• 批准号: 0855933
• 负责人: Daniel Snowden-Ifft
• 金额: $ 47.5万
• 依托单位: Occidental College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0855933&HistoricalAwards=false
• 关键词: RUI; DRIFT; Directional; Search; Dark

In this era of precision cosmology, measurements suggest that ordinary matter represents only a fraction of the total matter density in the Universe. The rest, whose effect we can only see gravitationally, appears to be dark. Particle physics models suggest that dark matter is composed of relic weakly interacting massive particles (WIMPs) left over from the Big Bang. Efforts to directly detect WIMPs are hampered by small interaction probabilities and large backgrounds that mimic expected dark matter signals. Fortunately, a number of unique dark matter signatures exist that can be used to discriminate against backgrounds and decisively identify WIMP interactions. The largest and most robust of these signatures, based on the predicted behavior of the WIMP flux as the Sun-Earth system moves through the galaxy, is a day-night modulation of nuclear recoil directions in the lab frame. The intellectual merit of this proposal resides in the Directional Recoil Identification From Tracks (DRIFT) Experiment's unique and powerful capabilities being brought to bear on one of the most important questions in science today. This award provides funds to support this group and to provide a new gas system to run with CS2-CF4 mixtures and the R&D for fiducializing DRIFT and retrofitting the present DRIFT detector with such a system. The Broader impacts of this work include the training of undergraduates in increasingly rare small-scale experiments, giving them exposure to a wide range of hardware and software experience. Finally, the DRIFT detector technology has promising applications to axion searches, Homeland Security and double-beta decay experiments.

在这个精确宇宙学时代，测量结果表明普通物质仅占宇宙总物质密度的一部分。其余的，我们只能在重力上看到其效果，似乎是黑暗的。粒子物理模型表明，暗物质由大爆炸中留下的遗物弱相互作用的巨大颗粒（WIMP）组成。直接检测WIMP的努力受到模仿预期暗物质信号的较小的相互作用概率和较大的背景。幸运的是，存在许多独特的暗物质特征，可用于区分背景并果断地识别WIMP相互作用。这些特征中最大，最强大的签名是基于WIMP通量的预测行为，因为太阳 - 地球系统通过银河系移动，是对实验室框架中核后坐方向的昼夜调制。该提案的智力优点在于来自轨道（漂移）实验的独特和强大能力的定向后坐力标识，以实现当今科学中最重要的问题之一。该奖项提供了支持该小组的资金，并提供了一种新的气体系统，以运行CS2-CF4混合物以及通过这样的系统进行基金化漂移和改造的R＆D。这项工作的更广泛的影响包括在越来越罕见的小型实验中培训本科生，使他们接触了广泛的硬件和软件体验。最后，漂移探测器技术在斧头搜索，国土安全性和双β衰减实验中有了有希望的应用。