Widening the search for Dark Matter and Physics beyond the Standard Model with direct detection experiments

通过直接探测实验将暗物质和物理学的搜索范围扩大到标准模型之外

• 批准号: ST/R003181/1
• 负责人: James Dobson
• 金额: $ 65.16万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FR003181%2F1
• 关键词: Widening; search; Dark; Matter; Physics

Everything we can see in the Universe is only a small fraction of its mass. Most of it, an incredible 85%, is 'dark' - and we know remarkably little about it. We can infer the role of this mysterious 'Dark Matter' in the early Universe when it allowed galaxies to form and we can observe its gravitational effects today as it holds the galaxies, including our own, together. Yet we cannot see it directly and have yet to make any detection that helps us understand its nature. Put simply, we know Dark Matter is there, but we do not know what it is! What we do know is that the Standard Model of particle physics that explains so accurately most of what we do observe cannot help us - it provides no candidates that fit the bill. The detection of Dark Matter will not only tell us what much of our Universe is made of, it will also open the door to physics beyond the Standard Model, bringing down the veil between us and a deeper understanding of the Universe and our place within it. The effort to detect Dark Matter is worldwide - it is truly one of the most important scientific missions of our time.Piecing together all the evidence, our best theories tell us Dark Matter is made up of tiny particles that that pervade the Universe but rarely interact - millions of Dark Matter particles are passing harmlessly through you as you read this right now. Just occasionally one of them may bounce off the nucleus of an atom, giving it a tiny kick of energy. Observing such a 'direct' scatter is the only way to be sure that we have seen Dark Matter from our own galaxy; born in the Big Bang and present ever since. But to have any hope of seeing such tiny, rare signals requires experiments like no other: large detectors, sensitive to the recoil of a single atom, constructed from the most radio-pure materials and buried deep under the surface of the Earth.LUX-ZEPLIN (LZ) will be the largest and most advanced experiment ever built in the direct search for Dark Matter. LZ will come online in 2019 and operate for 3 years in a former gold mine turned science laboratory 1.5 km underground in S. Dakota, USA. I am a leading researcher in the LZ experiment, responsible for the simulations that helped us to design it; that model the level of 'background' from Standard Model processes that may mask Dark Matter signatures; and that establish the experiment's science reach. LZ will be over 10 times more sensitive than earlier experiments and its unprecedented scale and ultra-low background environment will herald a new era in direct searches. In addition to exploring the bulk of the remaining uncharted territory in search of Weakly Interacting Massive Particles (WIMPs), the most popular candidate for dark matter, LZ will now have sensitivity and discovery potential to a whole host of equally well-motivated alternative (non-WIMP) Dark Matter candidates and other physics beyond the Standard Model. Key to these searches is my expertise in modelling background processes, in exploiting multiple signal channels across the full energy range available to LZ, and in developing software to recognise complex signals from wholly unexpected physics. I will take leading roles in the WIMP and alternative model searches from LZ to uncover groundbreaking discoveries.Alongside physics analyses and software, I have developed new hardware capability in the UK with world-class mass-spectrometry to measure trace radioactivity in materials. This technique is crucial to building any future experiment needed to confirm discovery, perform high-precision measurements of signal, or explore the last of the available parameter space available for WIMPs. Such an experiment would have incredible sensitivity to the alternative models and beyond Standard Model physics, such as neutrino-less double beta decay. My mass-spectrometry research will meet the stringent radio-purity needs for future generation experiments and feed the background model upon which all the science rests.

我们在宇宙中看到的一切都只是其质量的一小部分。其中大部分，令人难以置信的85%，是“黑暗的”——我们对它知之甚少。我们可以推断出这种神秘的“暗物质”在早期宇宙中所扮演的角色，当时它允许星系形成，我们今天可以观察到它的引力效应，因为它将包括我们自己的星系在内的星系聚集在一起。然而，我们无法直接看到它，也尚未做出任何有助于我们了解其性质的探测。简而言之，我们知道暗物质的存在，但我们不知道它是什么！我们所知道的是，粒子物理学的标准模型能够如此准确地解释我们所观察到的大多数现象，但它无法帮助我们——它没有提供符合要求的候选者。暗物质的探测不仅会告诉我们宇宙的大部分是由什么组成的，还会打开标准模型之外的物理学之门，揭开我们之间的面纱，让我们更深入地了解宇宙以及我们在宇宙中的位置。探测暗物质的努力是全世界的——它确实是我们这个时代最重要的科学任务之一。综合所有证据，我们最好的理论告诉我们，暗物质是由遍布宇宙但很少相互作用的微小粒子组成的——当你现在读到这篇文章的时候，数以百万计的暗物质粒子正在无害地穿过你的身体。它们中的一个偶尔会被原子核反弹，给原子核带来微小的能量。观测这种“直接”散射是确保我们从自己的星系看到暗物质的唯一方法；诞生于宇宙大爆炸之后一直存在但是，要想看到如此微小、罕见的信号，就需要进行独一无二的实验：大型探测器，对单个原子的反冲反应敏感，由最纯净的放射性材料建造，并深埋在地球表面之下。LUX-ZEPLIN （LZ）将是迄今为止在直接寻找暗物质方面建造的最大、最先进的实验。LZ将于2019年上线，并在美国南达科他州地下1.5公里处的一个前金矿改造的科学实验室中运行3年。我是LZ实验的首席研究员，负责帮助我们设计它的模拟；对可能掩盖暗物质特征的标准模型过程的“背景”水平进行建模；这就建立了实验的科学范围。LZ的灵敏度将是早期实验的10倍以上，其前所未有的规模和超低背景环境将预示着直接搜索的新时代。除了探索剩余的大部分未知领域，寻找弱相互作用大质量粒子（wimp），最受欢迎的暗物质候选者，LZ现在将具有灵敏度和发现潜力，以寻找一大批同样动机良好的替代（非wimp）暗物质候选者和其他超出标准模型的物理学。这些搜索的关键是我在建模背景过程方面的专业知识，在利用LZ可用的全能量范围内的多个信号通道方面的专业知识，以及在开发软件以识别完全意想不到的物理中的复杂信号方面的专业知识。我将在WIMP和LZ的替代模型搜索中担任领导角色，以发现突破性的发现。除了物理分析和软件之外，我还在英国开发了新的硬件能力，具有世界一流的质谱法来测量材料中的痕量放射性。这项技术对于建立任何未来的实验都是至关重要的，这些实验需要证实发现，进行高精度的信号测量，或者探索wimp可用的最后可用参数空间。这样的实验将对其他模型具有难以置信的灵敏度，并且超越了标准模型物理学，例如无中微子的双β衰变。我的质谱研究将满足下一代实验对放射性纯度的严格要求，并为所有科学所依赖的背景模型提供依据。

项目成果

Projected WIMP sensitivity of the LUX-ZEPLIN dark matter experiment

• DOI: 10.1103/physrevd.101.052002
• 发表时间: 2018-02
• 期刊: Physical Review D
• 影响因子: 5
• 作者: D. Akerib;C. Akerlof;S. Alsum;H. Araújo;M. Arthurs;X. Bai;A. Bailey;J. Balajthy;S. Balashov-S.-Balasho

Simulations of Events for the LUX-ZEPLIN (LZ) Dark Matter Experiment

LUX-ZEPLIN (LZ) 暗物质实验的事件模拟

• DOI: 10.48550/arxiv.2001.09363
• 发表时间: 2020
• 期刊: arXiv e-prints
• 作者: Collaboration T

First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment

• DOI: 10.1103/physrevlett.131.041002
• 发表时间: 2023-07-28
• 期刊: PHYSICAL REVIEW LETTERS
• 影响因子: 8.6
• 作者: Aalbers, J.;Akerib, D. S.;Zuckerman, A.
• 通讯作者: Zuckerman, A.

The LUX-ZEPLIN (LZ) radioactivity and cleanliness control programs

• DOI: 10.1140/epjc/s10052-020-8420-x
• 发表时间: 2020-11-10
• 期刊: EUROPEAN PHYSICAL JOURNAL C
• 影响因子: 4.4
• 作者: Akerib, D. S.;Akerlof, C. W.;Zarzhitsky, P.
• 通讯作者: Zarzhitsky, P.

Measurement of the gamma ray background in the Davis cavern at the Sanford Underground Research Facility

桑福德地下研究设施戴维斯洞穴中伽马射线背景的测量

• DOI: 10.1016/j.astropartphys.2019.102391
• 发表时间: 2020
• 期刊: Astroparticle Physics
• 影响因子: 3.5
• 作者: Akerib D