Collaborative Research: The DAMIC-M Detector to Search for Light Dark Matter

有强有力的宇宙学和天体物理学证据表明，冷暗物质是宇宙的主要组成部分。一个令人信服的解释是，迄今为止未知的弱相互作用大质量粒子(WIMP)的存在，世界范围内的一项实验工作正在进行中，以检验这一假说。暗物质(DM)的性质迄今难以捉摸，它构成了科学中最基本的问题之一。它作为一种未知粒子的发现将对我们对宇宙的理解产生深远的影响，并在粒子物理学和宇宙学方面开辟新的方向。这个项目的重点是DAMIC-M(电荷耦合器件中的暗物质)实验，该实验将通过探测电荷耦合器件(CCD)中轻DM诱导的核反冲和电子来超越重WIMP范式。这个重1公斤的探测器将通过国际合作安装在法国莫丹的南地形实验室。该奖项提供美国对DAMIC-M探测器建设的支持。身临其境的研究经验、当地社区的参与和创新的合作伙伴关系将把DM科学带给正式和非正式的受众。与专注于代表性不足群体的项目--例如芝加哥大学、费斯克-范德比尔特桥项目、华盛顿大学社区学院转学项目--合作开发的研究经验将增强研究生和本科生水平的多样性。当地社区将通过将空间探索者计划和STEM科学探究计划的高中URM学生整合到一个激励的研究环境中，通过加强URM中学生的RISE计划以及通过终身学习计划向老年人传播科学，在芝加哥广泛参与；在太平洋西北地区，通过科学合作伙伴计划，通过华盛顿大学的科学学校教师参与研究。DM科学将通过与阿德勒天文馆的合作伙伴关系接触到广泛和不同的受众，特别是与高影响力(每年50,000名游客)阿德勒天文对话计划，在该计划中，科学家与博物馆参观者直接互动。在这一新颖和非传统的应用中，电荷耦合器件通常用于天文望远镜的数字成像，电离电荷将在有史以来建造的具有精致空间分辨率的最大质量的电荷显示器中被探测到。这些器件的关键创新是对像素电荷的非破坏性、重复测量，这导致了对单电子的高分辨率检测和对光DM的前所未有的敏感性(~EV能量足以释放硅中的一个电子)。通过计算极低泄漏电流的探测器中的单个电荷--这一组合是任何其他DM实验所无法比拟的--DAMIC-M将在探索隐藏扇区方面向前跃进几个数量级，这一跳跃可能会得到偶然发现的奖励。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

There is strong cosmological and astrophysical evidence for cold dark matter as a major constituent of the universe. A compelling explanation is the existence of hitherto unknown Weakly-Interacting Massive Particles (WIMPs), and a world-wide experimental effort is on-going to test this hypothesis. The nature of Dark Matter (DM), so far elusive, constitutes one of the most fundamental questions in science. Its discovery as a yet unknown particle would have profound implications in our understanding of the universe, and open new directions in particle physics and cosmology. This project focuses on the DAMIC-M (Dark Matter In CCDs) experiment, which will search beyond the heavy WIMP paradigm by detecting nuclear recoils and electrons induced by light DM in charge-coupled devices (CCDs). The one-kg detector will be installed at the Laboratoire Souterrain de Modane, France by an international collaboration. This award provides US support for the construction of the DAMIC-M detector.Immersive research experiences, engagement of the local community and innovative partnerships will bring DM science to formal and informal audiences. Research experiences developed in collaboration with programs focused on underrepresented groups - e.g., U. Chicago and Fisk-Vanderbilt Bridge, the Community College Transfer Program at U. Washington - will enhance diversity at the graduate and undergraduate levels. The local community will be broadly engaged in Chicago by integrating high school URM students of the Space Explorers Program and of the STEM Science Inquiry and Research program in a stimulating research environment, by enhancing the RISE program for URM middle-school students and by communicating science to older adults via the Life-long Learning program; in the Pacific Northwest by engaging science school teachers in research at U. Washington through the Partners in Science program. DM science will reach broad and diverse audiences through partnerships with the Adler Planetarium, in particular with the high-impact (50,000 visitors/yr) Adler Astronomy Conversations program, where scientists interact directly with museum visitors.In this novel and unconventional use of CCDs, which are commonly employed for digital imaging in astronomical telescopes, the ionization charge will be detected in the most massive CCDs ever built with exquisite spatial resolution. The crucial innovation in these devices is the non-destructive, repetitive measurement of the pixel charge, which results in the high-resolution detection of a single electron and unprecedented sensitivity to light DM (~ eV energies are enough to free an electron in silicon). By counting individual charges in a detector with extremely low leakage current - a combination unmatched by any other DM experiment - DAMIC-M will take a leap forward of several orders of magnitude in the exploration of the hidden sector, a jump that may be rewarded by serendipitous discovery.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.