RUI: Test of Chiral Symmetry via the Primakoff Effect

RUI：通过 Primakoff 效应测试手性对称性

• 批准号: 0555524
• 负责人: Liping Gan
• 金额: $ 18.36万
• 依托单位: University of North Carolina at Wilmington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-05-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0555524&HistoricalAwards=false
• 关键词: RUI; Test; Chiral; Symmetry; via

This project is designed to integrate important contributions to the ongoing research at Jefferson lab with an educational experience for promising undergraduate students. A UNCW group with a team of undergraduate students and one full time faculty member has been actively involved in Jefferson lab research in the past four years. The primary goal of this project is to optimize the undergraduate experience while making important contributions to our understanding of the fundamental properties of QCD at low energy by studying the three neutral light pseudoscalar mesons, pion-zero, eta and eta (eta-prime). This research program consists of several experiments to measure the radiative decay widths and transition form factors of these three particles via the Primakoff Effect. The results of these measurements will have a significant impact on fundamental aspects of QCD. Of particular importance is a more accurate determination of the light quark-mass ratio and the eta-eta mixing angle. The transition form factors of these mesons at very small momentum transfer will provide model-independent extractions of the size of the electromagnetic interaction radii of mesons, and a low energy constant in the chiral Lagrangian.An experiment to measure the pion-zero two-photon decay width was successfully completed in fall 2004. The data analysis is currently in process. The advent of a 12 GeV electron beam at Jefferson Laboratory will make it possible to extend the measurement to the eta and eta particles. The UNCW group will continue working on existing pion-zero data analysis, play a leading role in optimizing the future experimental setup for the eta and eta by Monte Carlo simulation, and make significant contributions to the design and development of a high energy photon tagger and an existing electromagnetic calorimeter (HYCAL) upgrade. The PI will also initiate a new physics effort at Jlab to search for eta-mesic nuclei bound states. This research will engage undergraduate science majors as key contributors. The involvement of undergraduates has become one of the trademarks of the UNCW research group and matches the universitys commitment to provide a high quality undergraduate learning experience.

该项目旨在将杰斐逊实验室正在进行的研究的重要贡献与有前途的本科生的教育经验相结合。在过去的四年里，一个由本科生和一名全职教师组成的UNCW小组一直积极参与杰斐逊实验室的研究。本项目的主要目标是通过研究中性光赝标量介子，零介子，eta和eta (eta-prime)，在优化本科体验的同时，为我们理解低能QCD的基本性质做出重要贡献。本研究计划由几个实验组成，通过Primakoff效应测量这三种粒子的辐射衰减宽度和跃迁形状因子。这些测量的结果将对QCD的基本方面产生重大影响。特别重要的是更精确地确定轻夸克-质量比和eta-eta混合角。在非常小的动量转移下，这些介子的跃迁形式因子将提供与模型无关的介子电磁相互作用半径大小的提取，以及手性拉格朗日中的低能量常数。2004年秋天，我们成功地完成了测量介子-零双光子衰变宽度的实验。数据分析目前正在进行中。杰弗逊实验室12 GeV电子束的出现将使测量扩展到eta和eta粒子成为可能。UNCW小组将继续致力于现有的零介子数据分析，在优化eta和eta的蒙特卡罗模拟的未来实验设置方面发挥主导作用，并为高能光子标记器的设计和开发以及现有电磁量热计（HYCAL）的升级做出重大贡献。PI还将在Jlab发起一项新的物理工作，以寻找eta-mesic原子核束缚态。这项研究将吸引本科理科专业的学生作为主要贡献者。本科生的参与已经成为UNCW研究小组的标志之一，并且符合大学提供高质量本科学习体验的承诺。