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

TL;DR

This paper uses advanced many-body computational methods to set new, more stringent limits on CP-violating constants from the measured electric dipole moment of $^{199}$Hg, refining constraints on fundamental physics parameters.

Contribution

It provides improved theoretical calculations and tighter bounds on CP-violating coupling constants using relativistic many-body methods and experimental data.

Findings

Limits on T-PT coupling constant: $C_T < 2.31 imes 10^{-9}$

Limits on nuclear Schiff moment: $S<1.55 imes 10^{-12}|e|fm^3$

Refined constraints on $ heta_{QCD}$ and quark chromo-EDMs.

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 ($\alpha_d$) 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 $\alpha_d$ 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 $\theta_{QCD} < 2.12 \times 10^{-10}$ and the combined up and down quark chromo-EDMs $(-0.004 \tilde{d}_u + 0.020 \tilde{d}_d) < 1.15 \times 10^{-27} |e| cm$.