Research in Strong-Interaction Theory

要理解宇宙中物质的形成需要对原子核有深刻的了解。量子色动力学（QCD），夸克和胶子的相对论场论，被认为是强作用力的基础理论，因此也是原子核的基础理论。然而，QCD是非常复杂的，并且在描述普通原子核及其组成的低能下很大程度上没有解决。从几个角度对这个问题提出了攻击。强相互作用的“最简单”束缚系统是核子（质子和中子）和介子，它们组成原子核。俄亥俄州立大学率先采用新的光前场理论技术，直接解决这些系统的QCD问题。在普通的核现象中寻找夸克和胶子是一个巨大的挑战。从QCD到原子核的路径正在使用“有效场论”方法构建，该方法以低能粒子的形式提供了等效但易于处理的QCD描述。用相对论性描述核反应和结构，与实验联系起来。这项工作通过为实验分析提供工具，从而弥补了核现象和QCD之间的差距，然后反馈到对核及其子结构的进一步理解。

***9800964Clark Understanding the formation of matter in the universe requires a deep understanding of atomic nuclei. Quantum Chromodynamics (QCD), the relativistic field theory of quarks and gluons, is believed to be the underlying theory of the strong force and therefore of nuclei. However, QCD is extremely complex and is largely unsolved at the low energies relevant for describing ordinary nuclei and their constituents. Attacks on this problem from several perspectives are proposed. The "simplest" bound systems of the strong interaction are nucleons (protons and neutrons) and mesons, of which nuclei are composed. A direct attack on solving QCD for these systems is being mounted using new light-front field theory techniques pioneered at Ohio State. Finding quarks and gluons in ordinary nuclear phenomena is a great challenge. A path from QCD to nuclei is being constructed using "effective field theory" methods, which provide equivalent, but tractable descriptions of QCD in terms of low-energy particles. Contact with experiment is made using relativistic descriptions of nuclear reactions and structure. This work bridges the gap between nuclear phenomena and QCD by providing tools for the analysis of experiments, which then feed back to the further understanding of the nucleus and its substructure.