Theoretical Investigations in Hadron Physics

这项为期三年的理论物理研究计划在极小的距离内分离和分析了亚原子物质结构背后的各种物理机制，在那里可以分辨出夸克和胶子。要解释国家设施中的实验，如杰斐逊实验室(JLab)的CEBAF加速器和布鲁克海文的相对论重离子对撞机(RHIC)，需要确定以相对论量子色动力学(QCD)为基础的主要物理机制。在许多情况下，用格子计算方法对这一理论进行耗时的直接数值模拟必须得到建立在场论积分和微分方程式上的连续介质模型的补充。本项目将QCD最成功的连续介质模型之一推广到物理测量和现象的新领域，从而扩展了QCD模型的研究范围。其中包括含有一个或两个重夸克的介子的轴向反常、质量、衰变和跃迁形状因子对赝标介子味道混合的影响，以及用深度非弹性轻子散射测量的介子、介子和核子的夸克结构函数。更广泛的影响包括核物理和粒子物理的交叉受精，对JLab和RHIC实验设施的投资回报，以及通过研究生与本科教学相关的研究性培训将研究和教育结合起来。研究生与国内和国际知名科学家的互动是对国家研究和教育基础设施的贡献。PI用这个研究项目中的例子来说明量子力学和核物理与粒子物理核心研究生课程的关键要素。PI和一位同事为研究生和博士后助理主持了一门非正式的研讨会课程，讨论和介绍作为这项研究计划基础的QCD和场论的各个方面。与澳大利亚科学家现有的Linkage合作，加上美国国家科学基金会从国际科学与工程办公室为美墨双边合作提供的资金，将加强科学研究和教育方面的国际合作。

This three-year theoretical physics research program isolates and analyzes a variety of physical mechanisms underlying the structure of subatomic matter at the very small distances where quarks and gluons can be discerned. Interpretation of experiments at national facilities such as the CEBAF accelerator at the Jefferson Laboratory (JLab) and Brookhaven's Relativistic Heavy Ion Collider (RHIC) requires the identification of dominant physical mechanisms as grounded in the relativistic quantum field theory known as Quantum Chromodynamics (QCD). In many cases, the time-consuming direct numerical simulation of this theory by lattice computational methods must be complemented by continuum models built on the integral and differential equations of the field theory. The present project extends the reach of one of the most successful continuum models of QCD by generalizing it into new domains of physical measurements and phenomena. These include flavor mixing in pseudoscalar mesons influenced by the axial anomaly, masses, decays and transition form factors of mesons containing one or two heavy quarks, and the quark structure functions of pions, kaons, and nucleons as measured by deep inelastic lepton scattering. Broader impacts include the cross-fertilization of nuclear and particle physics, a return on the investment in the experimental facilities at JLab and RHIC, and integration of research and education through the research training of graduate students in connection with undergraduate teaching. The interactions of graduate students with scientists who are prominent nationally and internationally is a contribution to the nation's infrastructure for research and education. The PI uses examples from this research program to illustrate key elements of core graduate classes in Quantum Mechanics and Nuclear and Particle Physics. The PI and a colleague supervise an informal seminar course for graduate students and postdoctoral associates to discuss and present aspects of QCD and field theory that underlie this research program. An existing Linkage Collaboration with Australian scientists, together with NSF funding for the U.S.-Mexican bilateral collaboration from the Office of International Science and Engineering, will enhance international cooperation in science research and education.