Neutrino Physics with Liquid Argon Detectors: Entering the MicroBooNE Era

液氩探测器的中微子物理：进入 MicroBooNE 时代

• 批准号: 1403280
• 负责人: Mitchell Soderberg
• 金额: $ 56.47万
• 依托单位: Syracuse University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-15 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1403280&HistoricalAwards=false
• 关键词: Neutrino; Physics; Liquid; Argon; Detectors

One of the major intellectual achievements of the 20th century was the development of the Standard Model (SM) of particle physics. This model succeeded in classifying all of the elementary particles known at the time into a hierarchy of groups having similar quantum properties. The validity of this model to date was recently confirmed by the discovery of the Higgs boson at the Large Hadron Collider at CERN. However, the Standard Model as it currently exists leaves open many questions about the universe, including such fundamental questions as to why the Higgs mass has the value it has and why there is no antimatter in the universe. One of the primary areas to search for answers to these and other open questions about the universe, how it came to be and why it is the way it is, is to focus on a study of the properties of neutrinos and to use what we know and can learn about neutrinos as probes of science beyond the Standard Model. Neutrinos are those elementary particles that interact with practically nothing else in the universe. They have no electric charge and were once thought to be massless. Like other elementary particles, they were believed to have an antimatter counterpart, the antineutrino. Moreover, the Standard Model predicted that there were actually three different kinds of neutrinos that were distinguishable through the different interactions that they did undergo whenever there was an interaction. But recent measurements have totally changed our picture of neutrinos. We now know that neutrinos do have a mass and because they do, they can actually change from one type to another. Detailed measurements of these changes, along with other current neutrino experiments, form one of the most promising ways to probe for new physics beyond the Standard Model. Such measurements lie at the heart of this project.There is currently a large interest in experimental particle physics in Liquid Argon Time Projection Chambers (LArTPC) spurred in part by the proposed Long Baseline Neutrino Experiment (LBNE) project at Fermi National Accelerator Laboratory (FNAL) and in neutrino physics in general. This award supports work which refines LArTPC technology, using a test beam and at the MicroBooNE experiment at FNAL.LArTPC detector technology is scalable to the very large masses (perhaps 10 kiloTons) needed by next generation neutrino experiments and is capable of recording three-dimensional digital images of particle trajectories. The MicroBooNE will have an active volume of 80 tons of liquid argon and 8256 wires spread over three instrumented wireplanes making up the Time Projection Chamber. MicroBooNE will make a variety of interesting physics measurements, as well as serving as a proving ground for new hardware techniques relevant for future experiments. Among MicroBooNE's primary physics goals is to provide a cross-check of the "low-energy excess" of electron neutrino events previously identified by the MiniBooNE experiment. There have been recent "hints" that there may be a new type of neutrino, the so-called sterile neutrino. The MicroBoone experiment, with the superior LArTPC, should clarify the situation: either rule out or confirm the sterile neutrino evidence. The broader impact of this work will involve graduate students and undergraduates supported by this proposal receiving first-hand experience with High Energy Physics detector development, while also having access to MicroBooNE data that the graduate students will use for their dissertation analyses. The Syracuse group will continue with several outreach efforts as part of this proposal. The group maintains an outreach webpage that includes an "Ask-a-A-Physicist" questionnaire form as well as an active QuarkNet program.

世纪的主要学术成就之一是粒子物理学标准模型（SM）的发展。该模型成功地将当时已知的所有基本粒子分类为具有相似量子特性的组的层次结构。最近，欧洲核子研究中心的大型强子对撞机发现了希格斯玻色子，证实了这一模型的有效性。然而，目前存在的标准模型留下了许多关于宇宙的问题，包括为什么希格斯质量具有它的价值以及为什么宇宙中没有反物质等基本问题。对于这些和其他关于宇宙的开放性问题，宇宙是如何形成的，为什么会是这样，寻找答案的主要领域之一是专注于中微子性质的研究，并利用我们所知道的和可以了解的关于中微子的知识作为标准模型之外的科学探针。中微子是那些基本粒子，在宇宙中几乎不与其他任何东西相互作用。它们不带电荷，曾经被认为是无质量的。像其他基本粒子一样，它们被认为有一个反物质对应物，反中微子。此外，标准模型预测，实际上有三种不同类型的中微子，它们可以通过不同的相互作用来区分，无论何时发生相互作用。但是最近的测量已经完全改变了我们对中微子的看法。我们现在知道中微子确实有质量，因为它们有质量，它们实际上可以从一种类型变成另一种类型。对这些变化的详细测量，沿着目前的其他中微子实验，构成了探索标准模型之外的新物理学的最有前途的方法之一。目前，人们对液氩时间投影室（LArTPC）中的实验粒子物理学和中微子物理学有很大的兴趣，这部分是由费米国家加速器实验室（FNAL）提出的长基线中微子实验（LBNE）项目所激发的。该奖项支持在FNAL的MicroBooNE实验中使用测试束改进LArTPC技术的工作。LArTPC探测器技术可扩展到下一代中微子实验所需的非常大的质量（可能为10千吨），并且能够记录粒子轨迹的三维数字图像。MicroBooNE的有效体积为80吨液态氩，8256根导线分布在构成时间投影室的三个仪表线平面上。MicroBooNE将进行各种有趣的物理测量，并作为与未来实验相关的新硬件技术的试验场。MicroBooNE的主要物理学目标之一是对MiniBooNE实验先前确定的电子中微子事件的“低能过剩”进行交叉检查。 最近有“暗示”说可能存在一种新型中微子，即所谓的无菌中微子。MicroBoone实验使用了上级LArTPC，应该可以澄清这种情况：要么排除，要么确认无菌中微子的证据。这项工作的更广泛的影响将涉及本提案支持的研究生和本科生，他们将获得高能物理探测器开发的第一手经验，同时还将获得研究生将用于论文分析的MicroBooNE数据。锡拉丘兹小组将继续开展几项外联工作，作为这项提议的一部分。该小组维护了一个外展网页，其中包括一个“问一个物理学家”问卷表格以及一个活跃的QuarkNet程序。