Double Polarization Reactions with Gamma Rays and CP Violation Studies With Kaon Decays

伽马射线双偏振反应和 Kaon 衰变的 CP 破坏研究

• 批准号: 9901178
• 负责人: Marvin Blecher
• 金额: $ 31.25万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2003-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9901178&HistoricalAwards=false
• 关键词: Double; Polarization; Reactions; Gamma; Rays

9901178BlecherThe observable universe contains matter, but no antimatter. A satisfactory explanation of this feature does not exist. All solutions require new sources of time reversal violation. This means that there exist unseen reactions of elementary particles that proceed at different rates going forward in time as compared to going backward in time. One project of this proposal is to search for such a reaction via positive kaon decay at the KEK facility in Japan.Neutrons and protons, called nucleons, are with electrons the particles that make up ordinary matter. A complete quantitative description of their structure is wanting. Via the study of the interactions of polarized gamma rays with polarized nucleons, various structure dependent effects can be measured and compared with theory. The LEGS facility of Brookhaven National Laboratory has developed gamma ray beams of unprecedented polarization, and is developing HD ice targets that will provide the highest nucleon polarization. A large acceptance detector has been installed to measure the various final states such interactions lead to.

9901178布莱克可见的宇宙包含物质，但不包含反物质。对这一特征还没有一个令人满意的解释。所有解决方案都需要新的时间反转违法源。这意味着，基本粒子存在着看不见的反应，与时间倒退相比，它们在时间上以不同的速度前进。这个提议的一个项目是在日本的KEK设施中通过正克子衰变来寻找这样的反应。中子和质子，称为核子，是与电子一起组成普通物质的粒子。对它们的结构缺乏完整的定量描述。通过对极化伽马射线与极化核子相互作用的研究，可以测量各种结构相关效应，并与理论进行比较。布鲁克海文国家实验室的LEGS设备已经开发出前所未有的偏振伽马射线束，并正在开发将提供最高核子偏振的HD冰靶。已经安装了一个大型验收检测器来测量这种相互作用导致的各种最终状态。