Nuclear spin-dependent parity nonconservation in molecules

分子中核自旋依赖性宇称非守恒

• 批准号: 0457039
• 负责人: David DeMille
• 金额: --
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-06-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0457039&HistoricalAwards=false
• 关键词: Nuclear; spin; dependent; parity; nonconservation

This experimental research program will shed light on the nature of parity nonconserving (PNC) interactions inside the nucleus, via the study of nuclear anapole moments. A deviation of the measured results from theoretical expectations could serve as evidence for new phenomena at an energy scale beyond that directly accessible to any planned accelerator; or could change our understanding of how electroweak physics is modified in the presence of nuclear matter. The proposed technique is related to previous studies of atomic PNC, but uses diatomic molecules rather than atoms to achieve a dramatic increase in sensitivity. The small energy splittings and the narrow spectral lines associated with hyperfine/rotational structure in molecules enhance the size of weak interaction effects by several orders of magnitude. This will make it possible for the first time to observe nuclear spin-dependent PNC effects from many different nuclei, over a wide range of mass numbers A, carrying both valence protons and valence neutrons. The ability to combine many observations will make it possible to completely characterize the different contributions to nuclear spin-dependent PNC effects. The broader impact of the program will involve extensive student training as well as several collaborations. This award is funded jointly through the Atomic, Molecular, Optical and Plasma Physics Program and the Nuclear Physics Program in the Physics Division.

这项实验研究计划将揭示宇称非守恒（PNC）的性质的核内的相互作用，通过研究核的anapole时刻。测量结果与理论预期的偏差可以作为新现象的证据，其能量范围超过任何计划中的加速器直接可获得的能量范围;或者可以改变我们对在核物质存在下如何修改电弱物理的理解。所提出的技术与原子PNC的先前研究有关，但使用双原子分子而不是原子来实现灵敏度的急剧增加。与分子中的超精细/旋转结构相关的小能量分裂和窄谱线将弱相互作用效应的大小提高了几个数量级。这将使人们有可能第一次从许多不同的核，在很宽的质量数A范围内，同时携带价质子和价中子，观察核自旋相关的PNC效应。联合收割机的能力，许多观察将有可能完全表征不同的贡献核自旋相关的PNC效应。该计划更广泛的影响将涉及广泛的学生培训以及多项合作。该奖项由物理系的原子、分子、光学和等离子体物理计划以及核物理计划共同资助。