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arXiv · 1408.4337

Rigorous limits for hadronic and semi-leptonic CP-violating coupling constants from the electric dipole moment of $^{199}$Hg

Abstract

Relativistic many-body methods at different levels of approximations are employed to gain insights into the passage of the electron correlations from lower to higher levels in the accurate determination of the electric dipole polarizability ($α_d$) and electric dipole moment (EDM) due to the electron-nucleus tensor-pseudotensor (T-PT) and nuclear Schiff moment (NSM) interactions of the $^{199}$Hg ground state. Moreover, plausible reasons for the differences in the previous calculations are pointed out. Comparison between the calculated and experimental results of $α_d$ indicates that our EDM calculations are about 3\% accurate which in combination with the measured value of $^{199}$Hg EDM yield limits for the T-PT coupling constant $C_T < 2.31 \times 10^{-9}$ and the NSM $S<1.55 \times 10^{-12}|e|fm^3$. From this limit of $S$ and the latest nuclear structure calculation, we get improved limits for the strong CP violating parameter $θ_{QCD} < 2.12 \times 10^{-10}$ and the combined up and down quark chromo-EDMs $(-0.004 \tilde{d}_u + 0.020 \tilde{d}_d) < 1.15 \times 10^{-27} |e| cm$.

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Yashpal Singh, B. K. Sahoo. 2014-09-12. Rigorous limits for hadronic and semi-leptonic CP-violating coupling constants from the electric dipole moment of $^{199}$Hg. https://doi.org/10.1103/physreva.91.030501

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