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arXiv · 1608.07975

The cancellation mechanism in the predictions of electric dipole moments

Ligong Bian·Ning Chen
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Abstract

The interpretation of the baryon asymmetry of the Universe necessitates the CP violation beyond the Standard Model (SM). We present a general cancellation mechanism in the theoretical predictions of the electron electric dipole moments (EDM), quark chromo-EDMs, and Weinberg operators. A relative large CP violation in the Higgs sector is allowed by the current electron EDM constraint released by the ACME collaboration in 2013, and the recent $^{199}$Hg EDM experiment. The cancellation mechanism can be induced by the mass splitting of heavy Higgs bosons around $\sim\mathcal{O}(0.1-1)$ GeV, and the extent of the mass degeneracy determines the magnitude of the CP-violating phase. We explicate this point by investigating the CP-violating two-Higgs-doublet model and the minimal supersymmetric Standard Model. The cancellation mechanism is general when there are CP violation and mixing in the Higgs sector of new physics models. The CP-violating phases in this scenario can be excluded or detected by the projected $^{225}$Ra EDM experiments with precision reaching $\sim10^{-28}\,e\cdot{\rm cm}$, as well as the future colliders.

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Ligong Bian, Ning Chen. 2016-08-29. The cancellation mechanism in the predictions of electric dipole moments. https://doi.org/10.1103/physrevd.95.115029

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