Results are given from the next-generation search for T-violation in 205Tl, which is interpreted in terms of an electric dipole moment of the electron (de) using theory. The new experiment is a major upgrade of the apparatus used to set the previous best limit on de. Like its predecessor, it uses magnetic resonance with separated oscillating fields, laser optical pumping for state selection and analysis, and counter-propagating vertical atomic beams to control systematic effects arising from motional magnetic fields E × v/c. New to this incarnation are side-by-side atomic beam regions with common magnetic but opposite electric fields, and the addition of 23Na, with concomitant measurement equipment, to the atomic beams. The neighboring atomic beams provide common-mode noise rejection and an additional handle on some systematics. Simultaneous study of the sodium provides another handle, since it is insensitive to d e but susceptible to the same magnetic effects as thallium. Furthermore, sodium's two useful ground state hyperfine levels allow the separation of the two different types of motional field effects. The new result is d e = (6.8 ± 8.1) × 10−28 e cm. A detailed discussion of the experimental method is given. Several ancillary discoveries are also described, including a new kind of motional field systematic and a novel method for studying leakage/charging current effects, a general problem for experiments of this type.
展开▼
机译:下一代搜索 205 super> Tl中的T-违规给出了结果,该解释以电子(d e sub> italic>)。这项新实验是对d e sub> italic>设置先前最佳限值的仪器的重大升级。像其前身一样,它使用具有分离振荡场的磁共振,激光泵浦进行状态选择和分析,并垂直传播垂直原子束,以控制运动磁场产生的系统效应 E bold>× v bold> / c italic>。对这种化身的新发现是具有共同磁场但电场相反的并排原子束区域,以及伴随测量设备向原子束中添加的 23 super> Na。相邻的原子束可提供共模噪声抑制功能,并在某些系统上具有附加功能。钠的同时研究提供了另一个解决方案,因为它对d e sub> italic>不敏感,但易受与same相同的磁性作用。此外,钠的两个有用的基态超细水平允许分离两种不同类型的运动场效应。新结果是d e sub> italic> =(6.8±8.1)×10 −28 super> e italic> cm。给出了实验方法的详细讨论。还描述了一些辅助发现,包括一种新型的运动场系统和研究泄漏/充电电流效应的新方法,这是此类实验的一个普遍问题。
展开▼