Electromagnetic Properties and Hadronic Parity Violation in Lattice QCD

晶格 QCD 中的电磁特性和强子宇称破缺

• 批准号: 1515738
• 负责人: Brian Tiburzi
• 金额: $ 30万
• 依托单位: CUNY City College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1515738&HistoricalAwards=false
• 关键词: Electromagnetic; Properties; Hadronic; Parity; Violation

Quarks are elementary particles that are strongly bound inside protons and neutrons. The residual strong interactions between protons and neutrons give rise to all of nuclear physics, from the simplest nuclear reactions responsible for fusion, to the intricate structure of large unstable nuclei. In essence, nuclei are to the strong 'chromodynamic' force what molecules are to the electromagnetic force. Tremendous progress is being made by solving the theory of strong interactions numerically. Current computing power and algorithms have put one within reach of realistic computations. Quantitative knowledge of the strong force will ultimately render nucleons and nuclei into laboratories for investigating fundamental symmetries and probing the limits of the Standard Model of particle physics. The comprehensive research program of the PI will combine advances in theoretical physics and high-performance computing to help advance our knowledge about nucleons and nuclei to the most advanced level yet. Moreover, the scope of this program affords both student and post-doctoral researchers considerable opportunities for training in nuclear and computational science, two areas in which an advanced technical workforce is much needed.The scientific goal of this project is to study electromagnetic and parity-violating properties of strongly bound systems directly from Quantum Chromodynamics (QCD). The distribution of charge and magnetism within nucleons will be explored by calculating their magnetic moments and electromagnetic polarizabilities using lattice gauge theory. Effort will also be geared toward studying the electromagnetic structure of light nuclei and hyper-nuclei using lattice QCD techniques, including the challenge of reducing the quark mass. Manifestations of the weak interaction at low energies will additionally be investigated from QCD. The parity-violating component of non-leptonic weak interactions introduces hadronic parity violation, and probes quark-quark correlations deep within hadrons. Due to feasibility of lattice QCD computations in the isotensor channel, lattice renormalization of isotensor parity violation will be determined and electromagnetic mixing will be addressed for the first time. Novel methods will be sought for future lattice calculations in the remaining isospin channels.

夸克是一种基本粒子，它们被强烈地束缚在质子和中子内部。质子和中子之间的残余强相互作用产生了所有的核物理学，从最简单的核反应到聚变，再到大型不稳定核的复杂结构。本质上，原子核对于强色动力学力的作用就像分子对于电磁力的作用一样。通过数值求解强相互作用理论正在取得巨大的进展。目前的计算能力和算法已经使人们能够进行现实的计算。对强力的定量认识最终将使核子和原子核进入实验室，用于研究基本对称性和探索粒子物理学标准模型的极限。PI的综合研究计划将结合联合收割机在理论物理和高性能计算方面的进展，以帮助将我们对核子和原子核的认识提高到最先进的水平。此外，该项目的范围为学生和博士后研究人员提供了相当多的机会，在核科学和计算科学方面进行培训，这两个领域迫切需要高级技术人员。该项目的科学目标是直接从量子色动力学（QCD）研究强束缚系统的电磁和宇称违反性质。核子内的电荷和磁性分布将通过使用格点规范理论计算它们的磁矩和电磁极化率来探索。还将努力利用晶格QCD技术研究轻核和超核的电磁结构，包括减少夸克质量的挑战。在低能量下弱相互作用的表现将另外从QCD研究。非轻子弱相互作用的宇称破缺分量引入强子宇称破缺，并探测强子内部的夸克-夸克关联。由于格子QCD计算在等张量通道中的可行性，格子重整化的等张量宇称破坏将被确定和电磁混合将首次解决。新的方法将寻求未来的晶格计算在其余的同位旋通道。