Upgrades for an improved measurement of the EDM of $^{\mathrm{\mathbf{225}}}$\textbf{Ra}
ORAL
Abstract
If charge conjugation (C), parity (P) and time-reversal (T) symmetries, collectively form a good symmetry of nature, CPT, then T-violating phenomena would also violate CP. An Electric Dipole Moment (EDM) would violate time-reversal symmetry, and therefor EDMs provide a sensitive way for probing CP-violation that might explain the abundance of matter over anti-matter in the Universe. The $^{\mathrm{225}}$Ra atom (t$_{\mathrm{1/2}} \quad =$ 15 days, I $=$ 1/2) is a particularly attractive candidate for an EDM search in diamagnetic atoms due to its octupole deformed nuclear structure, nearly degenerate parity doublet ground state, and a large mass, that make it sensitive to T-violating interactions in the nuclear sector. Our latest measurement limits the atomic EDM of $^{\mathrm{225}}$Ra to be less than 1.4x10$^{\mathrm{-23}}$ e-cm (95{\%} C.L). Further experimental upgrades are being implemented including an electric field upgrade to enhance the EDM sensitivity and STIRAP for an improved spin precession detection scheme. With these upgrades in place our EDM sensitivity should increase by nearly two orders of magnitude and allow us to substantially improve constraints on certain T-violating processes within the nucleus.~This work is supported by the U.S. DOE, Office of Science, Office of Nuclear Physics, under contract DE-AC02-06CH11357 and the Michigan State University.
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