RUI: Parity Violation in Electron Scattering Experiments at JLab and Nucleon Structure

RUI：JLab 电子散射实验和核子结构中的宇称破坏

• 批准号: 0555555
• 负责人: Piotr Decowski
• 金额: $ 13.21万
• 依托单位: Smith College
• 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 2012-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0555555&HistoricalAwards=false
• 关键词: RUI; Parity; Violation; Electron; Scattering

The grant will support involvement of undergraduate women students in cutting edge experiments in one of the leading accelerator centers (Thomas Jefferson National Accelerator Facility in Virginia). The experiments will utilize parity violating polarized electron scattering to investigate nucleon and nuclear structure. A very tiny asymmetry in the scattering of polarized electrons with spins pointing along their motion and in opposite direction allows the separation of electromagnetic and weak interactions contributing to the scattering. These two interactions sense quark flavors in the nucleon, and neutrons and protons in the nucleus, with different strength. It opens the possibility to study in detail the quark flavor composition of the nucleon and neutron skin on the surface of a heavy nucleus. The measured asymmetry is extremely small and requires an unprecedented precision which puts planned experiments at limits of present technical capabilities.

该赠款将支持女本科生参与领先的加速器中心之一（弗吉尼亚州的托马斯杰斐逊国家加速器设施）的尖端实验。实验将利用宇称破坏极化电子散射来研究核子和核结构。极化电子的散射中的非常微小的不对称性，其自旋沿着它们的运动并且在相反的方向上指向，允许分离电磁和弱相互作用对散射的贡献。这两种相互作用以不同的强度感知核子中的夸克味道，以及原子核中的中子和质子。这为详细研究重核表面核子和中子皮的夸克味成分提供了可能。测量的不对称性非常小，需要前所未有的精度，这使得计划的实验处于目前技术能力的极限。