Collaborative Research: DarkSide-20k: A Global Program for the Direct Detection of Dark Matter Using Low-Radioactivity Argon

合作研究：DarkSide-20k：使用低放射性氩直接探测暗物质的全球计划

• 批准号: 1812453
• 负责人: ROBERT VOGELAAR
• 金额: $ 17万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2024-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1812453&HistoricalAwards=false
• 关键词: Collaborative; Research; DarkSide; 20k; Global

Multiple astronomical observations have established that about 85% 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. Deciphering the nature of this so-called Dark Matter is of fundamental importance to cosmology, astrophysics, and high-energy particle physics. A leading hypothesis is that it is comprised of Weakly Interacting Massive Particles, or WIMPs, that were produced moments after the Big Bang. If WIMPs are the dark matter, then their presence in our galaxy may be detectable via scattering from atomic nuclei in detectors located deep underground to help reject backgrounds due to cosmic rays. 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. This award is to support the NSF-funded DarkSide (DS) groups for the construction and operation of DarkSide-20k (DS-20k), a direct WIMP search using a Liquid Argon Time Projection Chamber (LAr TPC) with an active (fiducial) mass of 23 tons (20 tons).The LAr TPC relies heavily on the utilization of argon obtained from underground sources, or UAr. The planned Aria project for UAr purification may improve the worldwide availability of valuable stable rare isotopes such as O-18, N-15, and C-13, used for various medical, industrial and energy generation applications. The production of hundreds of tonnes of low-radioactivity UAr for DS-20k and for other technical uses requiring detection of Ar-37 for nuclear test ban verification, and Ar-39, for radiometric dating. Special E&O programs are planned with focus on educating K-12 teachers about basic physics and how it relates to dark matter detection, re-starting a summer school experience for high-school and undergraduate students, as well giving research opportunities to undergraduate students at participating underrepresented-minority serving institutions.DS-20k builds on the success of DarkSide-50 (DS-50), operating at LNGS since 2013, which produced two zero-background science results using atmospheric argon (AAr) and then underground argon (UAr) fills. DS-50 demonstrated an 39Ar reduction of 1400 in the UAr. Electron recoil (ER) background was shown to be completely suppressed in the region of interest, with discrimination better than 1 part in 1.5 x 10^7. These results demonstrated the ability of large LAr TPCs to operate in an "instrumental background-free mode" - a mode in which less than 0.1 events (other than actual nuclear recoils from elastic scattering of atmospheric and diffuse supernova background neutrinos) are expected in the region of interest for the planned exposure of DS-20k. DS-20k will have ultra-low backgrounds, with the ability to measure its backgrounds in situ, and sensitivity to WIMP-nucleon cross sections of 1.2 x 10^-47 cm2 (1.1 x 10^-46 cm2) for WIMPs of 1 TeV/c2 (10 TeV/c2) mass, to be achieved during a 5 yr run with exposure of 100 t yr.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.

多项天文观测已证实，宇宙中约 85% 的物质不是由正常原子组成，而一定是未被检测到的基本“暗物质”粒子，它们不发射或吸收光。破译这种所谓的暗物质的本质对于宇宙学、天体物理学和高能粒子物理学至关重要。一个主要的假设是，它由大爆炸后不久产生的弱相互作用大质量粒子（WIMP）组成。如果 WIMP 是暗物质，那么它们在我们银河系中的存在可以通过位于地下深处的探测器中原子核的散射来探测到，以帮助排除宇宙射线造成的背景。直接探测 WIMP 暗物质将解决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成分和粒子物理学标准模型之外的物理学提供了一个独特的窗口。该奖项旨在支持 NSF 资助的 DarkSide (DS) 小组建造和运营 DarkSide-20k (DS-20k)，这是一种使用液氩时间投影室 (LAr TPC) 和主动（基准）的直接 WIMP 搜索质量为 23 吨 (20 吨)。LAr TPC 严重依赖于从地下来源获得的氩气 (UAr) 的利用。计划中的 UAr 纯化 Aria 项目可能会提高宝贵的稳定稀有同位素（例如 O-18、N-15 和 C-13）在全球范围内的可用性，这些同位素可用于各种医疗、工业和能源发电应用。生产数百吨低放射性 UAr，用于 DS-20k 和其他需要检测 Ar-37（用于核试验禁令验证）和 Ar-39（用于放射性测年）的技术用途。计划开展特殊的 E&O 项目，重点是对 K-12 教师进行基础物理及其与暗物质探测的关系教育，为高中生和本科生重新启动暑期学校体验，并为本科生提供参与研究的机会DS-20k 建立在 DarkSide-50 (DS-50) 的成功基础上，自 2013 年以来在 LNGS 运行，利用大气氩产生了两项零背景科学成果(AAr)，然后填充地下氩气 (UAr)。 DS-50 证明 UAr 中的 39Ar 减少了 1400。电子反冲 (ER) 背景在感兴趣区域中被完全抑制，辨别力优于 1.5 x 10^7 中的 1 部分。这些结果证明了大型 LAr TPC 在“仪器无背景模式”下运行的能力，在这种模式下，预计在DS-20k 计划曝光的感兴趣区域。 DS-20k 将具有超低背景，能够原位测量其背景，并且对 1 TeV WIMP 的 WIMP 核子截面灵敏度为 1.2 x 10^-47 cm2 (1.1 x 10^-46 cm2) /c2 (10 TeV/c2) 质量，在 5 年运行期间达到 100 吨/年。该奖项反映了通过使用基金会的智力价值和更广泛的影响审查标准进行评估，NSF 的法定使命被认为值得支持。

项目成果

Separating $${^{39}\hbox {Ar}}$$ from $${^{40}\hbox {Ar}}$$ by cryogenic distillation with Aria for dark-matter searches

使用 Aria 通过低温蒸馏将 $${^{39}hbox {Ar}}$$ 与 $${^{40}hbox {Ar}}$$ 分离以进行暗物质搜索

• DOI: 10.1140/epjc/s10052-021-09121-9
• 发表时间: 2021-04
• 期刊: The European Physical Journal C
• 作者: Agnes, P.;Albergo, S.;Albuquerque, I. F. M.;Alexander, T.;Alici, A.;Alton, A. K.;Amaudruz, P.;Arba, M.;Arpaia, P.;Arcelli, S.;et al
• 通讯作者: et al

DarkSide-20k: A 20 tonne two-phase LAr TPC for direct dark matter detection at LNGS

DarkSide-20k：20 吨两相 LAr TPC，用于 LNGS 直接暗物质检测

• DOI: 10.1140/epjp/i2018-11973-4
• 发表时间: 2018-03
• 期刊: The European Physical Journal Plus
• 作者: Aalseth, C. E.;Acerbi, F.;Agnes, P.;Albuquerque, I. F.;Alexander, T.;Alici, A.;Alton, A. K.;Antonioli, P.;Arcelli, S.;Ardito, R.;et al
• 通讯作者: et al

Constraints on Sub-GeV Dark-Matter–Electron Scattering from the DarkSide-50 Experiment

DarkSide-50 实验对亚 GeV 暗物质的限制——电子散射

• DOI: 10.1103/physrevlett.121.111303
• 发表时间: 2018-09
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Agnes, P.;Albuquerque, I. F.;Alexander, T.;Alton, A. K.;Araujo, G. R.;Asner, D. M.;Ave, M.;Back, H. O.;Baldin, B.;Batignani, G.;et al
• 通讯作者: et al

Low-Mass Dark Matter Search with the DarkSide-50 Experiment

使用 DarkSide-50 实验进行低质量暗物质搜索

• DOI: 10.1103/physrevlett.121.081307
• 发表时间: 2018-08
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Agnes, P.;Albuquerque, I. F.;Alexander, T.;Alton, A. K.;Araujo, G. R.;Asner, D. M.;Ave, M.;Back, H. O.;Baldin, B.;Batignani, G.;et al
• 通讯作者: et al

Sensitivity of future liquid argon dark matter search experiments to core-collapse supernova neutrinos

未来液氩暗物质搜索实验对核心塌陷超新星中微子的敏感性

• DOI: 10.1088/1475-7516/2021/03/043
• 发表时间: 2021-03
• 期刊: Journal of Cosmology and Astroparticle Physics
• 影响因子: 6.4
• 作者: Agnes, P.;Albergo, S.;Albuquerque, I.F.M.;Alexander, T.;Alici, A.;Alton, A.K.;Amaudruz, P.;Arcelli, S.;Ave, M.;Avetissov, I.Ch.;et al
• 通讯作者: et al