Precision Measurement of Nuclear Magnetic and Electric Dipole Moments using Spin-Precession in Ultralow Fields

通过对极低磁场中极化惰性气体的核自旋进动的精确测量，我们打算解决基础物理学中的两个悬而未决的问题：宇宙中物质对反物质的支配地位的起源以及基本常数的时间稳定性的探索。129 π，d（π），这表明一个重要的CP破坏可能导致了今天宇宙中的重子-反重子不对称。假设的原子核电偶极矩与外加电场的相互作用将使旋进频率从纯拉莫尔频率偏移与d（π）成比例的量。利用~ 3 He-~（129）He共磁矩测量法，我们希望将目前公认的d（π）上限至少降低一个数量级，通过同时测量~ 3 He和~（129）He的进动，我们希望能最高精度地测量两个核磁矩的比值。通过这种方式，我们可以探测夸克质量的稳定性和量子色动标度参数的单位。这个项目与慕尼黑工业大学的Peter Fierlinger的nEDM-建议密切相关，我们在DFG优先计划的过程中与他合作。

By precision measurements of the nuclear spin precession of polarized noble gases in ultra-low magnetic fields, we intend to address two open problems in fundamental physics: the origin of the dominance of matter over antimatter in the universe and the probing of the temporal stability of fundamental constants.The existence of a finite electric dipole moment of a nucleus like 129Xe, d(Xe), would indicate a significant CP-violation that could have caused the baryon-antibaryon asymmetry in todays universe. The interaction of the postulated nuclear electric dipole moment with an additionally applied electric field would shift the precession frequency from the pure Larmor frequency by an amount that is proportional to d(Xe). By using 3He-129Xe comagnetometry, we expect to reduce the currently accepted upper limit for d(Xe) by at least one order of magnitude.By the simultaneous measurement of 3He and 129Xe precession, we intend to measure the ratio of the two nuclear magnetic moments with an utmost precision. In this way we can probe the stability of the quark mass and in units of the quantum chromdynamic scale parameter.This project is closely connected to the nEDM-proposal of Peter Fierlinger from TU Munich, with whom we have collaborated in the course of the DFG priority programme.