Electric dipole moment of $^{225}$Ra due to P- and T-violating weak interactions

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We report rigorous calculations of electric dipole moment (EDM) in $^{225}$Ra due to parity and time-reversal violating tensor-pseudotensor (T-PT) and nuclear Schiff moment (NSM) interactions between the electrons and nucleus by employing the relativistic all order coupled-cluster (RCC) methods at various levels of approximation.

• The most accurate EDM ($d_A$) results are obtained as $d_A=-10.04\times 10^{-20} C_T <\sigma_n>|e|cm$ and $d_A^{NSM}=-6.79 \times 10^{-17} S (|e|fm^3)^{-1} |e|cm$ with $C_T$ and $S$ are the T-PT coupling constant and NSM respectively.
• Due to exhaustive treatment of the electron correlation effects in these calculations, the EDM results for the corresponding T-PT and NSM interactions reduce by about 45\% and 23\%, respectively, from the previously known values.
• Nonetheless they are still found to be 2-3 times larger than the $^{199}$Hg results.