Collaborative Research: DRIFT-III: Engineering for A Large Directional Dark Matter Detector

合作研究：DRIFT-III：大型定向暗物质探测器的工程

• 批准号: 1103511
• 负责人: Daniel Snowden-Ifft
• 金额: $ 84万
• 依托单位: Occidental College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-15 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1103511&HistoricalAwards=false
• 关键词: Collaborative; Research; DRIFT; III; Engineering

In this era of precision cosmology, measurements suggest that ordinary matter (protons and neutrons) represents only a fraction of the total matter density in the Universe. The rest, whose effect we can see only gravitationally, is unknown in its nature and is termed Dark Matter. Particle physics models suggest that dark matter is composed of relic Weakly Interacting Massive Particles (WIMPs) left over from the Big Bang. Experimental efforts to directly detect WIMPs are challenging due to the predicted small interaction probabilities and the existence of large backgrounds that mimic the expected signal. However, 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 signature is the predicted dependence of the WIMP flux on the Sun-Earth velocity through the galaxy, yielding a day-night modulation of the nuclear recoil direction in the laboratory. Of current searches with directional detectors, the Directional Recoil Identification From Tracks (DRIFT) experiment is a leader, having a decade of experience. The intellectual merit of this proposal resides in DRIFT's unique and powerful capabilities being brought to bear on one of the most important questions in science today. These advances in background rejection, combined with the fact that further limit setting capabilities are hampered by the small volume of DRIFT-II, suggest that DRIFT should scale-up. This award will enable the collaboration to continue running DRIFT-II in the Boulby mine in England. In addition to running DRIFT-IId, these funds will provide hardware for a second detector, DRIFT-IIe.Broader impacts of this work include the training of a diverse set of undergraduates and graduate students (including underrepresented minorities) 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 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（质子和中子）仅占宇宙总物质密度的一小部分。其余的物质，我们只能通过引力才能看到​​其影响，其性质未知，被称为暗物质。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。由于预测的相互作用概率较小以及模拟预期信号的大背景的存在，直接检测 WIMP 的实验工作具有挑战性。然而，存在许多独特的暗物质特征，可用于区分背景并明确识别 WIMP 相互作用。最大、最稳健的特征是预测的 WIMP 通量对穿过星系的日地速度的依赖性，从而在实验室中产生核反冲方向的昼夜调节。在当前使用定向探测器进行的搜索中，轨道定向反冲识别（DRIFT）实验处于领先地位，拥有十年的经验。该提案的智力价值在于 DRIFT 独特而强大的能力，可以解决当今科学中最重要的问题之一。背景抑制方面的这些进步，再加上 DRIFT-II 小体积阻碍了进一步的限制设置能力，表明 DRIFT 应该扩大规模。该合同将使双方能够继续在英格兰 Boulby 矿运行 DRIFT-II。除了运行 DRIFT-IId 之外，这些资金还将为第二个探测器 DRIFT-IIe 提供硬件。这项工作的更广泛影响包括在日益罕见的小规模中培训不同的本科生和研究生（包括代表性不足的少数群体）实验，让他们接触到广泛的硬件和软件经验。最后，DRIFT 探测器技术在国土安全和双 β 衰变实验中具有广阔的应用前景。