Precision measurements with polarized spins

极化旋转的精确测量

• 批准号: 0801042
• 负责人: Ronald Walsworth
• 金额: $ 36万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2009-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0801042&HistoricalAwards=false
• 关键词: Precision; measurements; polarized; spins

This research program is aimed at performing three precision experimental searches for new physics beyond the standard model of particle physics. The experiments use a maser operating simultaneously with Xe-129 and He-3. By stabilizing one of the noble-gas masers to a frequency reference, the PI's group can control the environment of the masers and then use the other maser as a sensor for new physics. The experiments to be carried out include: (i) a sensitive test of the fundamental Lorentz invariance (one of the fundamental aspects of the theory of relativity) and CPT (Charge conjugation, Parity, and Time reversal) symmetry for the neutron; (ii) an order-of-magnitude improved search for the effects of torsion gravity, which arises if spacetime has a Riemann-Cartan geometry; and (iii) a sensitive search for anomalous spin-spin interactions in the neutron sector. For experiment (i) and (ii) the project is expected to provide an order-of-magnitude improvement compared to the best previous limits. Much of our understanding of fundamental physics would have to be radically altered if an effect is observed. Experiment (iii) will provide a first sensitive search of this effect.Broader impacts of the program include the application of the atomic physics based precision measurement techniques of this research into the development of novel biomedical imaging tools (for example magnetic resonance imaging (MRI) at low magnetic fields of hyperpolarized noble gas inhaled into human lungs), as well as the development of a high-sensitivity magnetometer using nitrogen vacancy centers in diamond. Other broader impacts include extensive student training with continued successful focus on inclusion and training in precision measurements techniques of students and postdocs who are members of underrepresented groups in science and engineering.

该研究计划旨在对粒子物理学的标准模型进行三个精确的实验搜索。 该实验使用MASER与XE-129和HE-3同时运行。 通过将贵族的一个masers稳定为频率参考，PI组可以控制Masers的环境，然后将另一个Maser用作新物理学的传感器。 要进行的实验包括：（i）对洛伦兹的基本不变性（相对论理论的基本方面之一）和CPT（电荷共轭​​，平等和时间逆转）的敏感测试； （ii）缩放命令的提高搜索扭转重力的影响，如果时空具有riemann-cartan几何形状，则会产生； （iii）对中子部门中异常自旋旋转相互作用的敏感搜索。 对于实验（i）和（ii），与以前的最佳限制相比，该项目有望提供改善的量顺序。如果观察到效果，我们对基本物理学的大部分理解都必须从根本上改变。 实验（III）将对这种效果进行首次敏感搜索。该程序的行为影响包括基于原子物理学的精确测量技术的应用，这本研究的新生物医学成像工具的开发（例如，磁共振成像（MRI）在低极化的贵重气体的低磁场上，吸入了人肺），以及使用钻石中的氮空位中心开发高敏性磁力表。 其他更广泛的影响包括广泛的学生培训，继续成功地关注精确度量测量技术的学生和培训，这些技巧是科学和工程领域代表性不足的学生的学生和博士后。