A Theoretical Study of Hadronic Interactions and the Structure of the Nucleon

强子相互作用和核子结构的理论研究

• 批准号: 0244822
• 负责人: John Londergan
• 金额: --
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0244822&HistoricalAwards=false
• 关键词: Theoretical; Study; Hadronic; Interactions; Structure

This renewal proposal requests continued NSF funding of a research program currently sup-ported by the grant NSF-PHY-0070368. The major proposed topics lie in the area of \quark{nuclear physics," to study the quark sub{structure of strongly interacting particles. Particularattention is on approximate symmetries of QCD, particularly favor and charge symmetry.Symmetry violation provides a \mirror" to identify and quantify non-perturbative physics.This research should shed light on the detailed properties of the fundamental constituents ofmatter, with emphasis on the validity of favor and charge symmetry, the spin dependenceof parton distributions, and nuclear modification of parton properties. One product of thisgrant would be a comprehensive review of charge symmetry at both low and high energies,emphasizing our current understanding of the role of the up-down quark mass difference ingenerating charge symmetry violation over a wide variety of energies and physical processes.Models developed by the PI will be employed to investigate recent neutrino results, which aresuggested to show physics beyond the Standard Model. The structure of baryon resonanceswill be investigated through a relativistic code developed explicitly to study these systems.New features of these calculations should allow a more realistic description of the structure ofresonances in the .25N system. It is also proposed to study binding and scattering of particlesin constrained 2-D systems, relevant to quantum wires and photonic crystals. Prior research inthis area culminated in a monograph published by Springer-Verlag. Continuing studies involvecollaboration with an experimental colleague combining theoretical studies of novel geometrieswith experiments on these systems.In all proposed areas, there is close linkage between theory and experiment. Some recentpredictions by the PI are being studied at facilities such as LEP, HERA and the Tevatron.The baryon resonance work proposed here is relevant to data taken at the CLAS detectorat Jefferson Lab. The PI is involved in studies for a possible new facility, an Electron-IonCollider (EIC), which was favorably assessed in the recent NSAC Long-Range Plan for nuclearphysics. The PI is a co-author on recent EIC planning efforts that include a Web site and CD-ROM containing a Whitepaper on EIC physics. The PI is Director of the Indiana UniversityNuclear Theory Center (NTC). Currently the NTC has four postdocs and visitors, three ofwhom are women. In several instances, women working at NTC have received joint supportfrom two or more sources, combining federal, university or foreign contributions. The PI hasset up international collaborations between the NTC and physics institutes in Australia, Japanand Germany. The PI has mentored 9 undergraduate researchers in summer REU programsduring the past 8 years. They have given talks on their research at subsequent workshopsand professional meetings, and have collaborated on publications with the PI. The researchproposed here will provide training and mentoring for both postdoctoral research associates,and undergraduate physics majors.

该更新提案要求NSF继续资助目前由资助NSF-PHY-0070368支持的研究计划。提出的主要课题是在夸克核物理领域，研究强相互作用粒子的夸克亚结构。特别关注QCD的近似对称性，特别是势对称性和荷对称性，对称性破缺为识别和量化非微扰物理提供了一面“镜子”，这一研究将揭示物质基本组成的详细性质，重点是势对称性和荷对称性的有效性，部分子分布的自旋依赖性，以及部分子性质的核修饰。这项资助的一个成果是全面回顾高能和低能的电荷对称性，强调我们目前对上下夸克质量差在各种能量和物理过程中产生电荷对称性破坏的作用的理解。PI开发的模型将被用来研究最近的中微子结果，这些结果被认为是超越标准模型的物理学。重子共振的结构将通过一个专门为研究这些系统而开发的相对论性程序来研究，这些计算的新特点将允许对.25N系统中的共振结构进行更真实的描述。本文还提出了研究约束二维系统中粒子的束缚和散射，这与量子线和光子晶体有关。先前在这一领域的研究在Springer-Verlag出版的一本专著中达到了顶峰。继续的研究涉及与实验同事的合作，将新几何的理论研究与这些系统的实验相结合。在所有提出的领域，理论与实验之间都有密切的联系。PI最近的一些预测正在LEP、HERA和Tevatron等装置上进行研究，这里提出的重子共振工作与杰斐逊实验室CLAS探测器上的数据有关。PI参与了一个可能的新设施的研究，一个电子离子对撞机（EIC），这是在最近的NSAC核物理长期计划的有利评估。PI是最近EIC规划工作的共同作者，其中包括一个网站和包含EIC物理白皮书的CD-ROM。PI是印第安纳州大学核理论中心（NTC）的主任。目前，全国过渡委员会有四名博士后和访问者，其中三名是妇女。在若干情况下，在全国过渡委员会工作的妇女得到了两个或两个以上来源的联合支助，包括联邦、大学或外国捐助。PI在NTC和澳大利亚、日本和德国的物理研究所之间建立了国际合作。在过去的8年里，PI已经指导了9名本科研究人员参加夏季REU项目。他们在随后的研讨会和专业会议上就他们的研究发表了演讲，并与PI合作出版了出版物。这里提出的研究将为博士后研究助理和本科物理专业提供培训和指导。