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.

在这个精确宇宙学的时代，测量表明普通物质仅占宇宙总物质密度的一小部分。其余的部分，我们只能通过引力才能看到​​其效果，看起来是黑暗的。粒子物理模型表明，暗物质是由大爆炸遗留下来的弱相互作用大质量粒子（WIMP）组成的。相互作用概率小和模仿预期暗物质信号的大背景阻碍了直接探测 WIMP 的努力。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识别 WIMP 相互作用。这些特征中最大、最稳健的特征是实验室框架中核反冲方向的昼夜调节，这是基于日地系统穿过银河系时 WIMP 通量的预测行为。该提案的智力价值在于轨道定向反冲识别（DRIFT）实验的独特而强大的功能，可以解决当今科学中最重要的问题之一。该奖项提供资金来支持该小组，并提供一种使用 CS2-CF4 混合物运行的新气体系统，以及用于基准化 DRIFT 和用此类系统改造现有 DRIFT 探测器的研发。这项工作的更广泛影响包括对本科生进行越来越罕见的小规模实验的培训，让他们接触到广泛的硬件和软件经验。最后，DRIFT 探测器技术在轴子搜索、国土安全和双 β 衰变实验方面具有广阔的应用前景。