Probing for N*s with Linearly Polarized Photons in Hall B of JLab

在 JLab 的 B 厅用线偏振光子探测 N*s

• 批准号: 0555497
• 负责人: Philip Cole
• 金额: $ 27万
• 依托单位: Idaho State University
• 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: 2006-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0555497&HistoricalAwards=false
• 关键词: Probing; Linearly; Polarized; Photons; Hall

The probe afforded by a beam of linearly-polarized photons allows one to gain access to several observables in photonucleon reactions, which otherwise would not be measureable. This polarization axis of the photon beam breaks the azimuthal symmetry of the reaction, thereby introducing an azimuthal dependence in the differential cross section. This additional information on the angular dependence opens the door to the measurement of a host of observables which are accessible only with a beam of linearly-polarized photons; consequently it provides important constraints on the nature of the photon-nucleon reaction. Such polarization observables are necessary for extracting the spin/parity of the broadly overlapping baryon resonances. Two PhD students at Idaho State University will analyze the g8b data set from Hall B of JLab. Their thesis topics will primarily focus on the search for baryon resonances (N*s) that decay though either the rho meson or hyperon channel, respectively.The PI has been very active in coordinating research efforts with nuclear physicists in Latin America. Over the past six years, he has been awarded five NSF grants, which serve to promote dialog among faculty members and students of North American and South American institutions. Through these efforts, he seeks to strengthen existing links and forge new ones within the broad scope of the international nuclear physics community. Such academic relationships, moreover, will further serve to strengthen the scientific research program between our respective continents. The PI expects to use this NSF award as a platform towards attracting additional grant money for these broader impact activities.

由一束线偏振光子提供的探针使人们能够接触到光子核反应中的几个可观察到的现象，否则这些现象是无法测量的。光子束的偏振轴破坏了反应的方位角对称性，从而在微分截面中引入了方位角依赖性。这种关于角依赖性的附加信息为测量大量只能用线性偏振光子束才能获得的可观测物打开了大门；因此，它对光子-核子反应的性质提供了重要的约束。这种极化观测对于提取广泛重叠重子共振的自旋/宇称是必要的。爱达荷州立大学的两名博士生将分析JLab B厅的g8b数据集。他们的论文主题将主要集中在寻找分别通过介子和超子通道衰变的重子共振（N*s）。PI一直非常积极地与拉丁美洲的核物理学家协调研究工作。在过去的六年中，他获得了五项NSF资助，旨在促进北美和南美机构的教师和学生之间的对话。通过这些努力，他力求在国际核物理学界的广泛范围内加强现有的联系并建立新的联系。此外，这种学术关系将进一步加强我们各自大陆之间的科学研究计划。PI希望利用这个国家科学基金会的奖励作为一个平台，为这些更广泛的影响活动吸引更多的拨款。