Studies of Basic Symmetries and Fundamental Constants with Muons and Pions

μ子和π介子的基本对称性和基本常数的研究

• 批准号: 0555199
• 负责人: Tim Gorringe
• 金额: $ 56.1万
• 依托单位: University of Kentucky Research Foundation
• 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: 2006-06-01 至 2010-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0555199&HistoricalAwards=false
• 关键词: Studies; Basic; Symmetries; Fundamental; Constants

This project is focused on the testing of basic symmetries,and determination of fundamental constants, of the standard model.The proposed research involves the muLan/muCap experiments atthe Paul Scherrer Institute, Switzerland, and expt. 869 at theTRIUMF facility, Canada. The experiments will determine the Fermiconstant of the electroweak interaction to part-per-millionaccuracy, the induced pseudoscalar coupling constant of theproton's weak interaction to six percent accuracy, and test isospinsymmetry in pion-nucleon interactions to high precision. Both themuLan experiment and the muCap experiment at PSI involve highprecision measurements of positive/negative muon lifetimes andutilize new technologies including an intense pulsed muon beam,novel detectors, and high-speed electronics and data acquisition.Expt. 869 utilizes a reconfigured RMC spectrometer as a pi0spectrometer for the investigation of the elementary interactionbetween pions and nucleons. Both muCap and expt 869 will addressthe realization of two important symmetries of quantum chromodynamics-- chiral symmetry and isospin symmetry -- in low energy interactionsof protons and neutrons. The determination of the Fermi constantby the muLan experiment will both determine a fundamental parameterfor all electroweak calculations and facilitate the precision testingof the standard model.The project includes several areas for broader impact. The PI willcontinue his involvement of physics majors, computer science graduatestudents and physics graduate students in both the experimental programand the related development of high-speed electronics and dataacquisition. The PI will also continue his efforts in the teaching ofsymmetry principles and conservation laws in classes for physicsand engineering majors. Moreover, the measurements themselves areof textbook quantities (e.g. the Fermi constant and the muon magneticmoment) and have broad impact in their own right.

该项目的重点是测试基本对称性，并确定标准模型的基本常数。拟议的研究涉及瑞士Paul Scherrer Institute的Mulan/Mucap实验。 869在加拿大Thetriumf设施。该实验将确定电动发电机相互作用的fermiconstant与零件数（每百万ic左）的相互作用，这是诱导的伪级耦合偶联常数的弱相互作用至6％的精度，并测试了Pion-Nucleon相互作用中的同性恋对称性。 Themulan实验和PSI的MUCAP实验均涉及对正/负MUON寿命进行高精度测量，并利用新技术，包括强烈的脉冲粘膜，新型探测器以及高速电子设备和数据采集。 869利用重新配置的RMC光谱仪作为PI0Spectrometer，用于研究乳腺和核子之间的基本相互作用。 MUCAP和Expt 869均可解决质量染色体动力学的两个重要对称性 - 手性对称性和同源对称性 - 质子和中子的低能相互作用。 Fermi Consancation的确定Mulan实验将确定所有electroweak计算的基本参数，并促进标准模型的精确测试。该项目包括一些更广泛影响的区域。 PI将与他参与物理学专业，计算机科学毕业生和物理学专业的研究生参与实验计划和高速电子产品的相关开发和DataAcquisition的相关开发。 PI还将继续在物理学和工程专业的课程中的教学原则和保护法教学方面的努力。此外，测量本身是教科书数量（例如费米常数和磁磁性），并且自身具有广泛的影响。