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arXiv · 1504.07477

First Measurement of the Atomic Electric Dipole Moment of $^{225}$Ra

R. H. Parker·M. R. Dietrich·M. R. Kalita·N. D. Lemke·K. G. Bailey·M. N. Bishof·J. P. Greene·R. J. Holt·W. Korsch·Z. -T. Lu·P. Mueller·T. P. O'Connor·J. T. Singh
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Abstract

The radioactive radium-225 ($^{225}$Ra) atom is a favorable case to search for a permanent electric dipole moment (EDM). Due to its strong nuclear octupole deformation and large atomic mass, $^{225}$Ra is particularly sensitive to interactions in the nuclear medium that violate both time-reversal symmetry and parity. We have developed a cold-atom technique to study the spin precession of $^{225}$Ra atoms held in an optical dipole trap, and demonstrated the principle of this method by completing the first measurement of its atomic EDM, reaching an upper limit of $|$$d$($^{225}$Ra)$|$ $<$ $5.0\!\times\!10^{-22}$ $e \cdot$cm (95$\%$ confidence).

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R. H. Parker, M. R. Dietrich, M. R. Kalita, N. D. Lemke, K. G. Bailey, M. N. Bishof, J. P. Greene, R. J. Holt, W. Korsch, Z. -T. Lu, P. Mueller, T. P. O'Connor, J. T. Singh. 2015-04-29. First Measurement of the Atomic Electric Dipole Moment of $^{225}$Ra. https://arxiv.org/abs/1504.07477

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