Nuclear Physics Equipment

核物理设备

• 批准号: ST/L005700/1
• 负责人: David Ireland
• 金额: $ 4.47万
• 依托单位: University of Glasgow
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2014
• 资助国家: 英国
• 起止时间: 2014 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FL005700%2F1
• 关键词: Nuclear; Physics; Equipment

Approximately 98% of the mass of nucleons, and therefore of the visible universe, emerges from the interactions among their constituents, the quarks and gluons. The Higgs mechanism, which gives mass to the bare quarks, is responsible for only a small fraction of the nucleon mass. The confinement of quarks within mesons and baryons is a direct consequence of their fundamental interactions. The field theory of the strong nuclear force, Quantum Chromodynamics (QCD), is now well established, and yet the phenomena described above cannot be understood from the QCD Lagrangian; they are emergent properties that arise from the unique complexity of these interactions. QCD is as yet intractable at the mass scale of nucleons and nuclei, so a clear picture of the fundamental nature of matter at these energies does not yet exist. However, this situation is set to change, and both theoretical and experimental developments in the coming decade are expected to revolutionise our understanding of nuclear matter within the context of QCD and the Standard Model. We have an ambitious plan of work that encompasses the development of research programmes from existing themes, possibilities for new physics measurements that have opened up recently, and the completion of physics projects from data that has been previously obtained. Our programme will build on the work of our previous consolidated grant and we will exploit the investment in manpower and equipment to address the current issues in our field at the highest possible level, at the world's top facilities. The challenges for the science programme are encapsulated by several key questions, which we group together as they roughly match the themes we have defined:* What is the mechanism for confining quarks and gluons in strongly interacting particles (hadrons)?* What is the structure of the proton and neutron, and how do hadrons get their mass and spin? * Can we understand the excitation spectra of hadrons from the quark-quark interaction? * Do exotic hadrons (multiquark states, hybrid mesons and glueballs) exist? * How do nuclear forces arise from QCD? * What is the equation of state of nuclear matter? * What is the nature of dark matter?We will address these questions by leading experimental programmes at two of the world's leading facilities:* Jefferson Lab, Newport News, Virginia, USA (JLab)* MAMI, Mainz, Germany:

核子质量以及可见宇宙质量的大约 98% 是由其成分夸克和胶子之间的相互作用产生的。希格斯机制为裸夸克提供质量，但只负责核子质量的一小部分。夸克被限制在介子和重子内是它们基本相互作用的直接结果。强核力场论量子色动力学（QCD）现已十分成熟，但上述现象无法从QCD拉格朗日来理解；它们是由这些相互作用的独特复杂性产生的自然属性。 QCD 在核子和原子核的质量尺度上仍然难以处理，因此尚不存在这些能量下物质基本性质的清晰图景。然而，这种情况将会发生变化，未来十年的理论和实验发展预计将彻底改变我们在 QCD 和标准模型背景下对核物质的理解。我们有一个雄心勃勃的工作计划，其中包括根据现有主题开发研究计划、最近开辟的新物理测量的可能性，以及根据先前获得的数据完成物理项目。我们的计划将建立在我们之前的综合赠款工作的基础上，我们将利用人力和设备方面的投资，在世界顶级设施中以尽可能高的水平解决我们领域当前的问题。科学计划的挑战由几个关键问题概括，我们将这些问题分组在一起，因为它们大致符合我们定义的主题：*将夸克和胶子限制在强相互作用粒子（强子）中的机制是什么？*结构是什么质子和中子，强子如何获得质量和自旋？ * 我们能否从夸克-夸克相互作用中理解强子的激发光谱？ * 奇异强子（多夸克态、混合介子和胶球）是否存在？ * QCD 核力是如何产生的？ * 核物质的状态方程是什么？ * 暗物质的本质是什么？我们将通过两个世界领先设施的领先实验项目来解决这些问题：* 美国弗吉尼亚州纽波特纽斯的杰斐逊实验室 (JLab)* 德国美因茨 MAMI：