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arXiv · 1811.12262

Wigner-Eckart Theorem and the False EDM of $^{199}$Hg

Wolfgang Klassen·Jeffery W. Martin·Guillaume Pignol
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Abstract

In neutron electric dipole moment experiments, 199Hg is used as a comagnetometer. The comagnetometer suffers from a false EDM arising in leading order from a gradient dBz/dz in the magnetic field. Our work concerns higher-order multipole corrections to the false EDM of 199Hg. We show that for spherical traps, all higher-order multipole are identically zero. We further show that for the usual cylindrical traps used in EDM experiments, selection of quasi-spherical dimensions for the trap can reduce the higher-order contributions. The results are another indication that trap geometry is an important consideration for experiments desiring to control this systematic effect.

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Wolfgang Klassen, Jeffery W. Martin, Guillaume Pignol. 2019-01-15. Wigner-Eckart Theorem and the False EDM of $^{199}$Hg. https://doi.org/10.1016/j.nima.2019.01.019

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