Measurement of the Permanent Electric Dipole Moment of the $^{129}$Xe Atom

F. Allmendinger; I. Engin; W. Heil; S. Karpuk; H. -J. Krause; B. Niederländer; A. Offenhäusser; M. Repetto; U. Schmidt; S. Zimmer

doi:10.1103/physreva.100.022505

arXiv · 1904.12295

Measurement of the Permanent Electric Dipole Moment of the $^{129}$Xe Atom

F. Allmendinger·I. Engin·W. Heil·S. Karpuk·H. -J. Krause·B. Niederländer·A. Offenhäusser·M. Repetto·U. Schmidt·S. Zimmer

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Abstract

We report on a new measurement of the CP-violating permanent Electric Dipole Moment (EDM) of the neutral $^{129}$Xe atom. Our experimental approach is based on the detection of the free precession of co-located nuclear spin-polarized $^3$He and $^{129}$Xe samples. The EDM measurement sensitivity benefits strongly from long spin coherence times of several hours achieved in diluted gases and homogeneous weak magnetic fields of about 400~nT. A finite EDM is indicated by a change in the precession frequency, as an electric field is periodically reversed with respect to the magnetic guiding field. Our result, $\left(-4.7\pm6.4\right)\cdot 10^{-28}$ ecm, is consistent with zero and is used to place a new upper limit on the $^{129}$Xe EDM: $|d_\text{Xe}|<1.5 \cdot 10^{-27}$ ecm (95% C.L.). We also discuss the implications of this result for various CP-violating observables as they relate to theories of physics beyond the standard model.

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F. Allmendinger, I. Engin, W. Heil, S. Karpuk, H. -J. Krause, B. Niederländer, A. Offenhäusser, M. Repetto, U. Schmidt, S. Zimmer. 2019-04-28. Measurement of the Permanent Electric Dipole Moment of the $^{129}$Xe Atom. https://doi.org/10.1103/physreva.100.022505

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