Polarized Electron Scattering from Nucleons and Nuclei

核子和原子核的极化电子散射

• 批准号: 0653615
• 负责人: David Armstrong
• 金额: $ 32万
• 依托单位: College of William and Mary
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2009-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0653615&HistoricalAwards=false
• 关键词: Polarized; Electron; Scattering; Nucleons; Nuclei

This grant supports the research of the Hadronic Physics group at the College of William and Mary. The group conducts experiments using the polarized electron beam available at the Thomas Jefferson National Accelerator Facility. These experiments utilize the minute violation of "mirror symmetry" in electron scattering, which occurs due to the presence of the weak neutral-current interaction, an otherwise unnoticeable contribution to the scattering process. This "parity-violation" technique is being used to probe the quark structure of protons and neutrons, to study the distribution of neutrons in a heavy nucleus (which has important implications for understanding neutron stars), and to search for possible new forces or new particles beyond those in the Standard Model of particle physics. The group is responsible for the design, construction and testing of large wire-chamber detectors required for the latter experiment, the equipment for which has been funded by an NSF Major Research Instrumentation grant.The grant supports 1.5 postdoctoral fellows and three graduate students. Substantial involvement of undergraduate students is also anticipated through senior research projects and the REU site program at William and Mary.

这笔赠款支持威廉玛丽学院强子物理小组的研究。该小组使用托马斯·杰斐逊国家加速器设施提供的偏振电子束进行实验。这些实验利用了电子散射中“镜面对称性”的微小违反，这是由于弱中性电流相互作用的存在而发生的，否则对散射过程的贡献是不明显的。这种“宇称破坏”技术被用来探测质子和中子的夸克结构，研究重核中中子的分布（这对理解中子星具有重要意义），并寻找粒子物理标准模型之外可能的新力或新粒子。该小组负责后一个实验所需的大型线室探测器的设计、建造和测试，该设备由美国国家科学基金会重大研究仪器补助金资助。该补助金支持 1.5 名博士后研究员和 3 名研究生。预计本科生将通过高级研究项目和威廉玛丽玛丽大学的 REU 现场项目进行大量参与。